Certification Program for
FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
OPERATIONAL MANUAL
APRIL 1981
ADDENDUM
Administered by
AIR-CONDITIONING AND REFRIGERATION INSTITUTE
4100 North Fairfax Dr. Suite 200 Arlington VA 22203
FOREWORD
This addendum to Operational Manual, OM-410, contains copies of forms needed for
participation in the ARI Certification Program for Forced-Circulation Air-Cooling and
Air-Heating Coils.
Participants can obtain a supply of these forms by sending a request to:
Director of Engineering
Air-Conditioning and Refrigeration Institute
4100 NORTH FAIRFAX DRIVE, SUITE 200 Χ ARLINGTON, VIRGINIA 22203
TABLE OF CONTENTS
FORM
TITLE
CHC-C2B...................................................................Acceptance of Certification
CHC-C2 .....................................................................Request for Approval of Laboratory
410-1 ..........................................................................Calculation Procedure to Determine
Fin Efficiencies and Metal
Thermal Resistances
410-2 ..........................................................................Calculation of Air-Side Resistances
from Steam and Water Coil Tests
410-3 ..........................................................................Calculation of Tube-Side Pressure
Drops from Steam and Water Tests
410-4 ..........................................................................Calculation of Refrigerant-Side
Thermal Resistances from Volatile
Refrigerant Coils Tests
410-5 ..........................................................................Suggested Form for Rating Calculation
Procedure for Sensible Heat Air
Coils
410-6 ..........................................................................Suggested Form for Rating Calculation
Procedure for Cooling and
Dehumidifying Coils
410-7 ..........................................................................Calculation of Heat Transfer Coefficient
and Friction Factor for Ethylene
Glycol Coils
410-8 ..........................................................................Suggested Form for Rating Calculation
Procedure for Sensible Heat Air Coils
with Ethylene Glycol Solutions
410-9 ..........................................................................Suggested Form for Rating Calculation
Procedure for Cooling and Dehumidifying
Coils with Ethylene Glycol Solutions
CHC-CF1 ...................................................................Production Coil Line Certification
HCC-2&3-M ..............................................................Report of Manufacturer's Shipments
EX-2-Q.......................................................................Report of Total Export Shipments
ACCEPTANCE OF CERTIFICATION
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
PARTICIPANT ________________________________________________________ DATE ___________________
Data submitted with respect to coil lines listed below have been accepted and these coils lines are hereby
released for certification.
Data relating to these coil lines as agreed upon by the ARI Air-Heating and Air-Cooling Coils Sub Section of
Air-Conditioning Heat Transfer Products Section will be published in the next issue or supplement of the
Directory of Certified Applied Air-Conditioning Products and will continue in succeeding issues until the coil
line is withdrawn from manufacture, or until the data is withdrawn for any reason as set forth in the License
Agreement.
You are authorized to apply the Certification Symbol to coils of these coil line, and to display the Certification
Symbol on specification sheets or other literature pertaining to the listed coil lines, as specified in the License
Agreement.
Coil
Type
Fluid (s)
Used
Catalog
Number
Issue
Date
(or Code)
Trade of Brand Names (s): ________________________________________________
SIGNED____________________________
Engineer
For ARI Use Only:
Submitted: ________________
Prepared by: ______________
Typed by: ________________
Proofed by: _______________
Listed: ___________________
By: ______________________
REQUEST FOR APPROVAL OF LABORATORY TO TEST
FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
We, the undersigned, hereby request the Air-Conditioning and Refrigeration Institute to approve our laboratory,
located at
for the purpose of testing Forced-Circulation Air-Cooling and Air-Heating Coils to qualify for ARI
Certification.
We certify that all testing will be done according to the testing codes and certified Rating Programs approved by
ARI.
Accompanying this request is the following information:
________________________________________________________________________________________
Company
By ___________________________________________
Officer
By_______________________________________
Chief Engineer or Laboratory Director
______________________________________________ Date _____________________________________
Title
______________________________________________
Date
Form CHC-C2
The above requirement for a laboratory has been met by the requesting company in regard to instruments,
equipment and laboratory.
This laboratory is hereby given general approval to conduct precertification check tests.
AIR-CONDITIONING AND REFRIGERATION INSTITUTE
By _____________________________________________
Director of Engineering
Date ____________________________________________
This laboratory has satisfactorily met the requirements of the precertification check test and is hereby approved
for testing and rating air-cooled and air-heating coils in accordance with ARI Standard 410-81, subject to
withdrawal if the quality of the laboratory is not maintained.
AIR-CONDITIONING AND REFRIGERATION INSTITUTE
By _________________________________________________
Director of Engineering
Date ________________________________________________
Form CHC-C2
CALCULATION PROCEDURE TO DETERMINE FIN EFFICIENCIES AND METAL THERMAL RESISTANCES
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY ___________________________________________________ DATE _____________________________
ITEM
NO.
GENERAL DESCRIPTION AND
CALCULATION PROCEDURE
DIMENSIONS
(Encircled items refer to
preceding item numbers)
1
Fin Type and Thickness Profile
--
2
As - Secondary Surface Area
(See Par. 3.9.3, ARI
sq ft
[m2]
NUMERICAL VALUE
Standard 410)
3
Ap - Primary Surface Area
(See Par. 3.9.3, ARI
Standard 410)
sq ft
[m2]
Ao - Total External Coil Surface
sq ft
[m2]
4
5
6
7
Area = ( ν2ο + ν3ο )
Di - Tube Inside Diameter
Nt - Total Number of Tubes in
Coil
⟨11⟩ x ⟨12⟩
π x ⟨6⟩
Lt - Fin Tube Length
in. [mm]
-in. [mm]
Ai - Total Internal Coil Surface
⟨11⟨5⟩ ⟩ ⟨x6⟩ ⟨⟨712
⟨5⟩ ⟨ 6⟩ ⟨ 7⟩ ⎤
⟩ ⟩⎡
Area =
⎢A i = 318,344 ⎥
45π.84
⎣
⎦
8
9
B - Surface Ratio = ν4ο / ν8ο
sq ft
[m2]
--
10
Df - Spiral Fin Outside Diameter
in. [mm]
*11
Lf - Fin Length Perpendicular to
Direction of Tubes
in. [mm]
*12
Ld - Fin Depth in Direction of
Air Flow
in. [mm]
*For non-circular shaped fins only
Sheet 1 of 5
ITEM
NO.
13
Form 410-1
GENERAL DESCRIPTION AND
CALCULATION PROCEDURE
DIMENSIONS
(Encircled items refer to
preceding item numbers)
xe - Outside Radius of Equivalent
Annular Area of NonCircular Fin or of Annular
or Spiral Fin
xe =
- for continuous
in.
[mm]
NUMERICAL VALUE
plate
fin
xe =
for individually
finned
tube
xe = ν10ο / 2 - for spiral fin
14
Do - Tube Outside Diameter
in. [mm]
15
Yf - Fin Thickness for Fin of
Uniform Thickness
in.
[mm]
16
xo - Fin Root Radius
xo = ν14ο + ν15ο
2
-
for plate
type fins
with collars not
touching
adjacent
fins
xD = ν14ο + 2 ν15ο 2
xo = ν14ο
2
in.
[mm]
for plate
type fins
with collars
touching
adjacent
fins
- for plate type
fins without
collars and
spiral fins
Form 410-1
ITEM
NO.
17
GENERAL DESCRIPTION AND
CALCULATION PROCEDURE
w - Height of Equivalent
or of Actual Annual Fin
w = ν13ο - ν16ο
18
DIMENSIONS
(Encircled items refer to
preceding item numbers)
xe/xo - Radius Ratio of Equivalent
Annular Fin
= ν13ο / ν16ο
in.
[mm]
--
NUMERICAL VALUE
19
kf – Fin Material Thermal
Conductivity (See Table
2, ARI Standard 410)
Btu per (hr)
(sq ft) (F) / (ft)
[W≅mm/m2≅ΕC]
20
kt – Tube Material Thermal
Conductivity (See Table
2, ARI Standard 410)
Btu per (hr)
(sq ft) (F) / (ft)
[W≅mm/m2≅ΕC]
21
Yr - Fin Thickness at Root of
Spiral Fins
in.
[mm]
R1D - for Dry Surface Coils
22
(hr) (F) (sq ft)
per Btu
[m2≅ΕC/W]
⎡c ⎤
⎣ ⎦
RaW ⎢ mo" ⎥ - for Wet Surface Coils
Note: Arbitrarily assume various
values, covering application ratings
fa - Air-Side Film Heat Transfer
Coefficient
Btu per
(hr) (sq ft) (F)
Where: faD = 1/ ν22ο - for
Dry Surface Coils
23
[W/m2 ≅ ΕC]
⎡ m" ⎤
⎥
⎢⎣ c p ⎥⎦
faW = 1/RaW ⎢
for Wet Surface
Coils
Fin Efficiency Parameter
24
--
for plate-type fins
for spiral fins
= ⟨17⟩
⎡
⎢= ⟨17⟩
⎣⎢
2 x ⟨ 23⟩ ⎤
⎥
⟨19⟩ x ⟨15⟩ ⎦⎥
GENERAL DESCRIPTION AND
CALCULATION PROCEDURE
ITEM
NO.
= ⟨17⟩
25
⟨ 23⟩
6 x ⟨19⟩ x ⟨15⟩
DIMENSIONS
(Encircled items refer to
⎡
2 x ⟨ 23⟩ ⎤
⟨ 23⟩
preceding
item⎢numbers)
= ⟨17⟩
⎥
6 x ⟨19⟩ x ⟨ 21⟩
⎢⎣
∅Ø - Mean Fin Efficiency
(See Figs. 10 and 11)
⟨19⟩ x ⟨ 21⟩ ⎦⎥
--
NUMERICAL VALUE
η 0 - Total Surface Effectiveness
26
--
= ( ν25ο x ν2ο ) + ν3ο
ν4ο
27
Rf – Thermal Resistance of Fin
Based on Total Surface
Effectiveness
⎡1 − ⟨ 26⟩ ⎤ ⎡ 1 ⎤
⎥ ⎢ ⟨ 23⟩ ⎥
⟨ 26⟩
⎦⎣
⎦
⎣
= ⎢
(hr) (sq ft) (F)
per Btu
[m2 ≅ ΕC/W]
Rt – Thermal Resistance of Tube
28
29
⟨9⟩ ⟨5⟩ ⎛ ⟨14⟩ ⎞ ⎡ ⟨9⟩ ⟨5⟩ ⎛ ⟨14⟩ ⎞⎤
⎟⎥
⎟ ⎢=
⎜ Ln
=
⎜ Ln
24 ⟨ 20⟩ ⎜⎝
⟨5⟩ ⎟⎠⎦
⟨5⟩ ⎟⎠ ⎣ 2 ⟨ 20⟩ ⎜⎝
RmD - Total Metal Resistance of
Fin and Tube
= ν27ο + ν28ο
30
RaD + RmD - Combined Air Film
Plus Metal Thermal
Resistance for Dry
Surface Coils
= ν22ο + ν29ο
Plot (RaD + RmD) vs RaD ( ν30ο) vs
31
32
(hr) (sq ft) (F)
per Btu
[m2 ≅ ΕC/W]
(hr) (sq ft) (F)
per Btu
2
[m ≅ ΕC/W]
(hr) (sq ft) (F)
per Btu
[m2 ≅ ΕC/W]
--
--
--
--
--
--
--
--
--
--
ν22ο ) on rectilinear coordinates,
as shown in Fig. 1
Plot RaD vs fa ( ν29ο vs ν23ο) on
on rectilinear coordinates,
as shown in Fig. 2
SIGNED ______________________________________________ TITLE ____________________________________
NOTE:
Alternate Method to Determine Mean Fin Efficiency by Fin Segmentation
A more accurate, but more involved, method of calculating ∅ and Rf for non-circular shaped fins is described as
Method (2), pages 313-315 in Reference A9 of ARI Standard 410. The mean values of ∅, as determined by
this alternate method, will be somewhat lower than those calculated by the simpler, equivalent annular area
method given in the above procedure.
For non-circular fin designs of large size, in combination with thin, low thermal conductivity fin material, this
alternate method is recommended. The difference in ∅, as calculated by the two methods, also becomes greater
as the fin becomes more oblong. If this alternate method is used, it is recommended that the fin efficiency, ∅,
for each of the individual fin sectors be based on data by K. A. Gardner (Reference A8 of ARI Standard 410),
rather than that given in Reference A9.
Where this alternate method is used, please include all necessary information and calculations and attach them
to this form.
CALCULATION OF AIR-SIDE RESISTANCES FROM STEAM AND WATER COIL TESTS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY ____________________________________________________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
DATE _______________________________
COIL LINE __________________________________ COIL TYPE ______________________
COIL SURFACE ________________________________________________________________
GENERAL PROCEDURE
1
1
2
2
2
3
3
3
-
4
4
-
5
4
--
Sheet 1 of 12
ITEM DESCRIPTION
ITEM NO.
FULLYWETTED
SURFACE
1
(Encircled items refer to
preceding item numbers)
DIMENSIONS
1
AO - Total External Coil Surface
(See Form 410-1)
sq ft
[m2]
2
Di - Tube Inside Diameter (See Form 410-1)
in.
[mm]
3
B - Surface Ratio (See Form 410-1)
--
4
Nc - Number of Tube Circuits in Coil
--
5
5
Aix - Total Cross-Sectional Fluid Flow Area
Inside Tubes = 0.00545 (ν2ο) 2 x ν4ο
[Aix] = 7.85 x 10 –7 (ν2ο) 2 x ν4ο]
6
6
6
Nr
6a
6a
6a
Ls - Straight Tube Length Per Tube Pass
COIL PHYSICAL DATA
STEAM
COILS
NUMERICAL VALUES
GENERAL
CATEGORY
DRY
SURFACE
WATER COILS
- Coil Depth in Rows
sq ft
[m2]
-in.
[mm]
Form 410-
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
8
8
-
9
9
-
-
10
6
9
-
-
-
11
-
10
12
-
11
13
-
12
14
7
-
-
8
13
-
-
-
15
9
14
16
-
15
17
10
16
-
-
-
18
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
7
GENERAL
CATEGORY
7
LABORATORY TEST OBSERVATION AND CALCULATIONS OBTAINED FROM
ASHRAE STANDARD 33-78, FORMS 33TD-1, -2, -3
5
Sheet 2 of 12
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
DIMENSIONS
7
pS
- Average Absolute Static Pressure at
Test Coil
8
tl
- Entering Air Dry-Bulb Temperature
F [ΕC]
9
t 'l
- Entering Air Wet-Bulb Temperature
F [ΕC]
10
hl
- Entering Air Enthalpy
11
t2
- Leaving Air Dry-Bulb Temperature
12
h2
- Leaving Air Enthalpy
13
twl
- Entering Water Temperature
F [ΕC]
14
tw2
- Leaving Water Temperature
F [ΕC]
15
ww
- Rate of Water Flow
16
tvm
- Mean Saturated Steam Temperature in
Coil Circuit
17
qs
- Average Sensible Heat Capacity
Btuh [W]
18
qr
- Average Total Heat Capacity
Btuh [W]
19
va
- Standard Air Face Velocity
ft per min
[m/s]
20
twm
- Mean Water Temperature Inside Tubes
= 0.5 (ν13ο) + (ν14ο)
21
)Pst
- Isothermal Dry Surface Air-Side
Friction at Standard Conditions
in. water
[Pa]
22
)Psw
- Wet Surface Air-Side Friction at
Standard Conditions
in. water
[Pa]
1
2
3
4
IN. Hg abs
[Kpa abs]
Btu per lb
dry air
[KJ/Kg]
F [ΕC]
Btu per lb
dry air
[KJ/Kg]
lb per hr
[g/s]
F
[ΕC]
F
[ΕC]
Form 410-2
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
17
19
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
23
qS/qt - Sensible Heat Ratio = ν17ο / ν18ο
If << 0.95, coil surface is all
wet or partially dry.
DIMENSIONS
1
2
3
4
--
If ≥≧ 0.95, coil surface is fully dry.
11
18
19
20
-
24
CALCULATIONS DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
-
Vw
- Average Standard Water Velocity
Inside =
Tubes
25
)tm
⎡
⎤
⟨15⟩
⎢v w =
⎥
1,000,000 x ⟨5⟩ ⎦
⎣
- Logarithmic Mean Temperature Difference between Air and Heating or
Cooling Fluid
=
=
ν15ο
224,500 x ν5ο
⟨11⟩ − ⟨8⟩
⎡ ⟨16⟩ − ⟨8⟩ ⎤
In ⎢
⎥
⎣ ⟨16⟩ − ⟨11⟩ ⎦
ft per sec
[m/s]
F
[ΕC]
- For Steam Coils
(⟨8⟩ − ⟨14⟩ ) − (⟨11⟩ − ⟨13⟩ )
⎡ ⟨8⟩ − ⟨14⟩ ⎤
In ⎢
⎥
⎣ ⟨11⟩ − ⟨13⟩ ⎦
For Thermal Counterflow Water
Coils
If other than thermal counterflow, determine logarithm mean
temperature difference from Flgs.
13, 14 or 15.
Form 410-2
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
13
-
*
-
-
-
21
21
22
22
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
20
26
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
12
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
R
- Overall Thermal Resistance Between Air
and Heating or Cooling Fluid
= ν1ο x ν25ο
ν17ο
27
Plot R vs Va on logarithmic coordinates as
shown in Fig. 3. This curve is used in
obtaining steam coil application ratings.
28
DIMENSIONS
1
2
3
4
--
--
--
--
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
--
Btu per (hr)
(sq ft) (F)
[W/m2 ≅ ΕC]
29
Tube-Side Film Thermal Resistance
Rv = ν3ο /2000 - For Steam [Rv = 3 /11364]
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
Rw = ν3ο/28n - For Cold and Hot Water
* These items apply when steam coil tests are used to determine RaD for hot water ratings.
Form 410-2
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
ITEM NO.
--
21a
21a
28a
Cpw – Specific Heat of Water – at ν20ο
--
21b
21b
28b
kw – Thermal Conductivity of Water – at ν20ο
--
21c
21c
28c
Φw – Absolute Viscosity of Water – at ν20ο
--
21d
21d
28d
ttw – Average Tube Wall Temperature (Assumed)
For chilled water coils, initially assume
ttw is 5ΕF to 10ΕF greater than ν20ο
--
21e
21e
28e
Φtw – Absolute Viscosity of Water – at ν28dο
lb/? – ft
[mPa Αs]
--
21f
21f
28f
Gw – Mass Velocity of Water = ν15ο/ν5ο
lb/? – ft2
[g/s Α m2]
--
21g
21g
28g
Raw – Reynolds Number for Water = ν2ο x ν28fο
12 x ν28cο
--
--
21h
21h
28h
Ls/D: = Ratio of Tube Length to Diameter = ν6aο
ν2ο
--
--
21i
21i
28i
Jw - Colburn Heat Transfer Factor for Water from
Fig. 17 using ν28gο and ν28hο 9or calculate
from equation ? on Fig. 17)
--
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
GENERAL
CATEGORY
WATER COILS
DIMENSIONS
Btu/lb Α ΕF
[KJ/kg Α ΕC]
Btu
? Α ft Α ΕF
[w/m Α ΕC]
lb/? Α ft
[mPa Α s]
ΕF
[ΕC]
1
2
3
4
--
--
--
--
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
21j
--
21k
21k
--
21l
21l
--
21m
21m
--
21n
21n
--
23a
--
--
--
28a
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
21j
GENERAL
CATEGORY
--
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
DIMENSIONS
28j
Prw – Prandtl Number for Water = ν28aο x ν28cο
ν28bο
--
28k
Prw2/3 = ν28jο 2/3
--
28l
(:tw/:w) Α14 – Viscosity Ratio = (ν28eο/ν28cο) Α14
--
28m
Stw = Stanton Number for Water =
ν28jο
ν28kο x ν28lο
--
2
3
4
Btu/? Α ft2 Α ΕF
[w/m2 Α ΕC]
28n
fw = Film Heat Transfer Coefficient for Water
= ν28mο x ν28aο x ν28fο
30a
ttw ⟨ Average Tube Wall Temperature (calculated)
For chilled Water Coils = ν20ο + ν25ο ν29ο
ν29ο + ν30ο
ν30aο must equal ν28dο within ∀ 10ΕF [∀5.6C], if not
assume a new value for ν28dο and repeat calculations thru
ν30aο
ΕF
[ΕC]
37a
ttw
ΕF
[ΕC]
Average Tube Wall Temperature (calculated)
For chilled Water Coils = ν20ο + ν29ο (ν37ο - ν20ο)
ν29ο + ν34ο
ν37aο must equal ν28dο within ∀ 10ΕF [∀5.6C], if not
assume a new value for ν28dο and repeat calculations thru
ν30aο
1
Form 410-2
GENERAL PROCEDURE
GENERAL
CATEGORY
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
TO SOLVE FOR
TO SOLVE FOR
ROWS DEEP
CAPACITY
(qs)
(Nr)
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
NUMERICAL
VALUES
DIMENSIONS
STEAM
COILS
HOT OR
COLD
WATER
COILS
--
23a
--
23a
30a
Cpw – Specific Heat of Water at ν28ο
--
23b
--
23b
30b
kw -- Thermal Conductivity of Water at ν28ο
--
23c
--
23c
30c
Φw – Absolute Viscosity of Water at ν28ο
--
23d
--
23d
30d
ttw – Average Tube Wall Temperature (assumed)
- For chilled water coils, initially assume ttw is 5ΕF to
10ΕF greater than ν28ο
- For hot water coils, initially assume ttw is 10ΕF to 20ΕF
less than ν28ο
--
23e
--
23e
30e
Φtw = Absolute Viscosity of Water – at ν30dο
--
23f
--
23f
30f
Gw – Mass Velosity of Water = ν29ο/ν11ο
--
23g
--
23g
30g
Raw – Reynolds Number for Water = ν10ο x ν30fο
12 x ν30cο
--
23h
--
23h
30h
Ls/D: = Ratio of Tube Length to Diameter = ν12ο
ν10ο
--
23i
--
23i
30i
Jw – Colburn Heat Transfer Factor for Water from Fig. 17
using ν30gο and ν30hο (or calculate from equation ? on Fig. 17)
--
ITEM NO.
HOT OR
COLD
WATER
COILS
WATER RATING PARAMETERS
STEAM
COILS
Btu/lb Α ΕF
[KJ/kg Α ΕC]
Btu
h Α ft Α ΕF
[w/m Α ΕC]
lb/h Α ft
[mPa Α s]
ΕF
[ΕC]
lb/h Α ft
[mPa Αs]
lb/h – ft2
[g/s Α m2]
--
Form 410-5
HOT OR
COLD
WATER
COILS
STEAM
COILS
HOT OR
COLD
WATER
COILS
--
23j
--
23j
--
23k
--
23k
--
23l
--
23l
--
23m
--
23m
--
23n
--
23n
--
24
--
--
--
--
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
GENERAL PROCEDURE
GENERAL
CATEGORY
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
TO SOLVE FOR
TO SOLVE FOR
ROWS DEEP
CAPACITY
(qs)
(Nr)
– Prandtl Number for Water = ν30aο x ν30cο
ν30bο
NUMERICAL
VALUES
DIMENSIONS
Prw
30k
Prw 2/3 - = (ν30jο) 2/3
--
30l
(Φtw/Φw) .14 – Viscosity Ratio = (ν30eο/ν30cο) .14
--
30m
Stw
– Stanton Number for Water =
ν30iο
ν30kο x ν30lο
--
30n
fw
= Film Heat Transfer Coefficient for Water
= ν30mο x ν30aο x ν30fο
24
31
Rw
– Water Film Thermal Resistance = ν4ο/ν30nο
Btu/h – ft2 - ΕF
[w/m2 Α ΕC]
h Α ft2 Α ΕF/Btu
[m2 Α Εc/w]
35a
42a
ttw
= Average Tube Wall Temperature (Calculated)
CALCULATIONS TO
SOLVE FOR COIL
CAPACITY (qs)
WATER RATING PARAMETERS
30j
For chilled water coils ≅ ν28ο + ν31ο x ν39ο
ν33ο x ν35ο
For hot water coils ≅ ν28ο - ν31ο x ν39ο
ν33ο x ν35ο
ν42aο must equal ν30dο within ∀ 10 ΕF [∀5.6 ΕC]
for chilled water coils and ∀20 ΕF [∀11.1 ΕC] for
hot water coils. If not, assume a new value for ν30dο
and repeat calculations thru ν42aο
--
ΕF
[ΕC]
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
23
GENERAL
CATEGORY
*
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
30
RaD + RmD - Combined Air Film Plus Metal
Thermal Resistance
*
24
¤23
*
25
-
-
26
24
-
-
25
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
= ν26ο - ν29ο
DIMENSIONS
1
2
3
4
--
--
--
--
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
Plot ν30ο vs ν19ο on logarithmic
coordinates as shown in Fig. 4. This
curve is used in obtaining application
ratings for all sensible heat coils
except steam coils.
31
RaD
– Air Film Thermal Resistance for Dry
Surface (From Fig. 1, knowing ν30ο )
32
Plot RaD vs Va on logarithmic coordinates as shown in
Fig. 4. This curve is used in obtaining
application ratings for all sensible heat coils
except steam coils.
33
faD
34
– Air-side Heat Transfer Coefficient
1
1
for Dry Surface =
=
RaD
ν31ο
RmD – Total Metal Thermal Resistance of Fin
and Tube (Assuming dry surface, obtain from
Fig. 2 with ν33ο)
* These items apply when steam coil tests are used to determine RaD for hot water ratings.
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
--
Btu per (hr)
(sq ft) (F)
[W/m2 ≅ ΕC]
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
¤ For fully-wetted coils, read value of RaD from Fig. 4 as determined from dry coil tests.
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
-
-
26
35
hm
- Mean Air Enthalpy = 0.5 (ν10ο + ν12ο)
-
-
27
36
C
- Approximate Coil Characteristic
-
-
-
-
-
-
-
-
28
29
30
31
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
ν29ο + ν34ο
=
0.243
37
tsm
ν31ο
⎡
⟨ 29⟩ + ⟨34⟩ ⎤
⎥
⎢C =
1.018 ⟨31⟩ ⎦
⎣
- Approximate Mean Coil Surface
Temperature (From Fig. 9 with ν20ο ,
ν35ο , and ν36ο)
38
m" / c p -Approximate Air-Side Heat Transfer
DIMENSIONS
Btu per lb
dry air
[KJ/Kg]
(lb) (F)
per Btu
[Kg ≅ ΕC/KJ]
F
[ΕC]
--
Multiplier for Wet Surface Coils
(From Fig. 8 with ν7ο and ν37ο)
39
40
RaW
faW
- Air Film Thermal Resistance for Wet Surface
Note: Assume this value for trial and
error solution. Suggest initial
value be same as ν31ο.
- Approximate Air-Side Heat Transfer
Coefficient for Wet Surface = ν38ο / ν39ο
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
Btu per (hr)
(sq ft) (F)
[W/m2 ≅ ΕC]
-
-
32
41
RmW - Total Metal Thermal Resistance of Fin
and Tube for Wet Surface (From
Fig. 2 with ν40ο)
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
1
2
3
4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
-
33
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
DIMENSIONS
ν29ο + ν41ο
42
C
- Coil Charasteric =
0.243
ν39ο
-
34
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
⎡
⟨ 29⟩ + ⟨ 41⟩ ⎤
⎢C =
⎥
1.018 ⟨39⟩ ⎦
⎣
-
43
t "l
(lb) (F)
per Btu
- Entering Air Dew Point Temperature
(From Psychrometric Chart with ν7ο,
ν8ο, and ν9ο)
[Kg ≅ ΕC/KJ]
F
[ΕC]
Calculation of Dew Point Temperature
for Nonstandard Air Pressure*
⎡ (p − p' ) ( t1 − t 'l ) ⎤
p v = p' − ⎢ s
⎥
2830 − 1.44 t
⎥⎦
⎣⎢
⎡
⎡ (p − p' ) ( t1 − t 'l ) ⎤ ⎤
⎢ p v = p' − ⎢ s
⎥⎥
'
⎢⎣
⎢⎣ 1548.4 − 1.33 t l ⎥⎦ ⎥⎦
Where: ps = Air Pressure -------p = Saturation Vapor
Pressure at t l'
from Steam
Tables-----------p v = Saturation Vapor
Pressure at Dew
Point
Temperature-----
Jordon & Priester, Refrigeration and Air Conditioning. 2nd Edition, 1956
in. Hg abs
[Kpa abs]
1
2
3
4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
-
-
35
36
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
CALCULATIONS TO DETERMINE HEAT TRANSFER
COEFFICIENTS FOR USE IN APPLICATION RATINGS
-
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
t "l = Dew Point Temperature Is
Saturation Temperature
Corresponding to
Saturation Vapor Pressure,
pv, from Stream Tables ---44
tsl -
Coil Surface Temperature on Entering
Air Side (From Fig. 9 with ν10ο, ν14ο,
and ν42ο unless ν7ο varies more than
∀0.3 in. Hg [∀1.014 Kpa] from 29.92 in.
Hg [101.325 Kpa]. If it does, then
determine ts1 by trial and error using
equation:
DIMENSIONS
F [ΕC]
F
[ΕC]
ts1 = tw2 + C (h1 - hs1) .
Correct h 2l for ν7ο and use ν10ο ,
ν14ο, and ν42ο.
For fully wetted coil, ν43ο ≧ ν44ο.
If ν43ο < ν44ο, coil is partially wet and
calculation procedures may be determined
from Form 410-6.)
45
hs1 -
Saturated Air Enthalpy at ν7ο and
ν44ο
Btu per lb
dry air
[KJ/Kg]
1
2
3
4
STEAM
COILS
HOT OR
COLD
WATER
COILS
--
35a
--
--
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
STEAM
COILS
GENERAL PROCEDURE
50a
CALCULATIONS TO SOLVE FOR ROWS DEEP
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
TO SOLVE FOR
TO SOLVE FOR
ROWS DEEP
CAPACITY
(qs)
(Nr)
ttw
– Average Tube Wall Temperature (Calculated)
For chilled water coils ν28ο + ν31ο x ν44ο
ν33ο x ν50ο
For hot water coils ν28ο - ν31ο x ν44ο
ν33ο x ν50ο
NUMERICAL
VALUES
DIMENSIONS
ΕF
[ΕC]
ν50aο must equal ν30dο within ∀ 10ΕF [5.6ΕC]
for chilled water coils and ∀ 20ΕF [11.1ΕC] for
hot water coils. If not, assume a new value for ν30dο
and repeat calculations thru ν50aο
-
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
VOLATILE
COLD WATER
REFRIGERANT
COILS
COILS
GENERAL PROCEDURE
PARTIALLY
WET
SURFACE
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
FULLY
WET
SURFACE
31a
-
-
47a
Cpw - Specific Heat of Water - at ν46ο
31b
31b
-
-
47b
kw
31c
31c
-
-
47c
Φw - Absolute Viscosity of Water – at ν46ο
31d
31d
-
-
47d
ttw
31e
31e
-
-
47e
Φtw
- Absolute Viscosity of Water – at ν47dο
lb/h ≅ ft
[mPa ≅ s]
31f
31f
-
-
47f
Gw
- Mass Velosity of Water = ν32ο/ν13ο
lb/h ≅ ft2
[g/s ≅ m2]
31g
31g
-
-
47g
Raw
- Reynolds Number for Water = ν9ο x ν47fο
ν12ο x ν47cο
31h
31h
-
-
47h
Ls/D1 = Ration of Tube Length of Diameter = 10
9
--
31i
31i
-
-
47i
jw
--
CALCULATIONS TO SOLVE FOR ROWS DEEP
ITEM NO.
PARTIALLY
WET
SURFACE
31a
GENERAL
CATEGORY
FULLY
WET
SURFACE
NUMERICAL
VALUES
- Thermal Conductivity of Water – at ν46ο
- Average Tube Wall Temperature (assumed)
- For chilled water coils, initially assume ttw is 5ΕF to 10ΕF
greater than ν46ο
- Colburn Heat Transfer Factor for Water from Fig. 17
using ν47gο and ν47hο (or calculate from equation
above on Fig. 17)
DIMENSIONS
Btu/lb ≅ ΕF
[KJ/kg ≅ ΕC]
Btu
h ≅ ft ≅ ΕF
[w/m ≅ ΕC]
lb/h ≅ ft
[mPa ≅ s]
ΕF
[ΕC]
--
-
31k
31k
-
-
31l
31l
-
-
31m
31m
-
-
31n
31n
-
-
36a
36a
-
-
36b
36b
-
-
36c
36c
-
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
-
GENERAL
CATEGORY
FULLY
WET
SURFACE
31j
RATING CONDITIONS
& DATA COMPUTATIONS
PARTIALLY
WET
SURFACE
31j
GENERAL PROCEDURE
RATING PARAMETERS
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
VOLATILE
COLD WATER
REFRIGERANT
COILS
COILS
- Prandtl Number for Water = ν47aο x ν47cο
ν47bο
NUMERICAL
VALUES
DIMENSIONS
--
47j
Prw
47k
Prw 2/3= (ν47jο) 2/3
--
47l
(Φtw/Φw) .14 - Viscosity Ratio = (ν47eο/ν47cο) .14
--
47m
stw
= Stanton Number for Water =
47n
fw
= Film Heat Transfer Coefficient for Water
= ν47mο x ν47aο x ν47fο
52a
hm
- Mean Air Enthalpy ≅ (ν26ο + ν30ο)/2
52b
tsm
- Mean Surface Temperature from Fig. 9 using
ν52aο, ν52ο and ν46ο
ΕF
[ΕC]
52c
ttw
- Average Tube Wall Temperature (Calculated)
ΕF
[ΕC]
≅ ν46ο +
ν48ο
ν48ο + ν51ο
ν47Iο
ν47kο x ν47lο
(ν52bο - ν46ο)
ν52cο must equal ν47dο within ∀ 10ΕF [∀5.6 ΕC], if not
assume a new value for ν47dο and repeat calculations thru
ν52cο
--
Btu/h ≅ ft2 ≅ ΕF
[w/m2 ≅ ΕC]
Btu/lb
[KJ/Kg]
34
35
GENERAL
CATEGORY
42
42
RATING CONDS
AND DATA
COMPUTATIONS
33
34
35
43
44
45
43
44
45
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFACE
32
48
49
RATING PARAMETERS
33
PARTIALLY
WET
SURFACE
32
GENERAL PROCEDURE
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
VOLATILE
COLD WATER
REFRIGERANT
COILS
COILS
Tube-Side Thermal Resistance
Rw
= ν4ο/ν47nο For Water Coils
Rr
- From Fig. 6 with ν45ο for Volatile Refrigerant Coils
RaD
- Air Film Thermal Resistance for Dry Surface
(From Fig. 5 or 6 with ν16ο)
50
RaW
- Air Film Thermal Resistance for Wetted
Surface (From Fig. 5 or 6 with ν16ο)
51
RmD - Metal Thermal Resistance for Dry Surface
(From Fig. 2 at fa = 1/ν49ο)
NUMERICAL
VALUES
DIMENSIONS
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
36
36
46
46
52
Approximate Coil Characteristic = ν48ο + ν51ο
0.243 x ν50ο
(lb) (F)
per Btu
[Kg ≅ ΕC/KJ]
⎡ ⟨ 48⟩ + ⟨51⟩ ⎤
⎥
⎢=
⎣ 1.018 x ⟨50⟩ ⎦
Note: This approximate coil characteristic is used to obtain
RmW in ν63ο .
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
-
-
41
42
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
CALCULATIONS TO DETERMINE
HEAT TRANSFER
COEFFICIENTS FOR USE IN
APPLICATION RATINGS
-
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
50
Assume other values for ν39ο and repeat procedure through
DIMENSIONS
1
2
3
4
--
-
-
-
-
ν49ο. Plot values of ν49ο vs ν39ο as shown in Fig.
12a. Two or more points shall be plotted so that Ao lies
between calculated values of Ac .
51
RaW
- Air Film Thermal Resistance for Wet Surface
The point on the curve (Fig. 12a) as plotted in ν50ο ,
where Ac = Ao determines the RaW value which corresponds to ν19ο.
(hr) (sq ft)
(F) per Btu
[m2 ≅ ΕC/W]
-
-
43
52
Plot RaW vs Va (ν51ο vs ν19ο) on logarithmic coordinates
-
-
-
-
as shown in Figs. 5 and 6.
If the RaW curve is within ∀5 percent of the RaD curve,
RaD may be used to obtain application ratings for the
wetted surface portiono f all cooling and dehumidifying
coils.
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
-
-
-
38
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
37
46
CALCULATIONS TO DETERMINE
HEAT TRANSFER
COEFFICIENTS FOR USE IN
APPLICATION RATINGS
-
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
ts2
- Coil Surface Temperature on Leaving Air-Side
(From Fig. 9 with ν12ο , ν13ο , and ν42ο unless
DIMENSIONS
F
[ΕC]
ν7ο varies more than ∀0.3 in. Hg [∀1.014 Kpa]
from 29.92 in. Hg [101.325KPa]. If it does, then
determine ts2 by trial and error using equation:
ts2 = tw1 + C (h2 – hs2) .
Correct hs2 for ν7ο and use ν12ο , ν13ο , and ν42ο .)
47
hs2
Saturated Air Enthalpy at ν7ο and ν46ο
Btu per lb
dry air
[KJ/Kg]
1
2
3
4
-
-
39
48
Δhm - Logarithmic Mean Enthalpy Difference between
Air Stream and Coil Surface
=
(⟨10⟩ − ⟨ 45⟩ ) − (⟨12⟩ − ⟨ 47⟩ )
⎡ ⟨10⟩ − ⟨ 45⟩ ⎤
In ⎢
⎥
⎣ ⟨12⟩ − ⟨ 47⟩ ⎦
Btu per lb
dry air
[KJ/Kg]
Note: See Typical Thermal Diagram at end of Form.
-
-
40
49
Ac
=
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
- Calculated External Surface Area
0.243 ⟨39⟩ x ⟨18⟩ ⎡
1.018 ⟨39⟩ x ⟨18⟩ ⎤
⎢A c =
⎥
⟨ 48⟩
⟨ 48⟩
⎣
⎦
sq ft
[m2]
GENERAL PROCEDURE
NUMERICAL VALUES
TEST RUN NUMBER
27
44
ITEM NO.
CALCULATIONS OF COIL GENERAL
CATEGORY
AIR-SIDE PRESSURE
DROP
?
FULLYWETTED
SURFACE
STEAM
COILS
DRY
SURFACE
WATER COILS
53
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
Coil Air-Side Pressure Drop per Row Deep at Standard
Conditions
For dry surface: )pst = ν21ο/ν6ο
Nr
For fully-wetted surface: )pst = ν22ο/ν6ο
Nr
DIMENSIONS
in. water
per row
deep
[Pascal per
row deep]
1
2
3
4
?
28
45
54
Plot ν53ο vs ν19ο on logarithmic coordinates as shown in
--
-
-
-
-
Figs. 3, 4, 5, and 6, depending on coil type. Plot both
dry and wet surface pressure drop in Figs. 5 and 6.
These curves are used for application ratings.
SIGNED _____________________________________________________________
TITLE ____________________________________________________
TEMPERATURE OR ENTHALPY
TYPICAL THERMAL DIAGRAMS FOR STEAM AND WATER COILS
tw1
Sat. Steam Cond. Temp.
tvm
tvm
tw2
t2
t2
tl
tl
SURFACE
CALCULATION OF TUBE-SIDE PRESSURE DROPS FROM STEAM AND WATER TESTS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY ____________________________________________________________________
WATER
COILS
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL VALUES
TEST RUN NUMBER
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
COIL LINE _______________________________
GENERAL
CATEGORY
SOLUTION
PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
DATE _______________________________
DIMENSIONS
in.
[mm]
1
1
DI
- Tube Inside Diameter
2
2
2
Nt
- Total Number of Tubes In Coil
--
3
3
3
Nc
- Number of Tube Circuits in Coil
--
4
4
4
Aix
- Total Cross-Sectional Fluid Flow Area
5
5
6
6
7
7
COIL PHYSICAL DATA
1
Inside Tubes = 0.00545 (ν1ο) 2 x ν3ο
[Aix
Lx
- Straight Tube Length Per Pass
6
Kb
- Equivalent Length of Coil Circuit Per
Return Bend
7
Le
- Total Equivalent Length of Coil Circuit
⎛
⎜⎜ ⟨5⟩
⎝
[m2]
= 7.85 x 10- 7 (ν1ο) 2 x ν3ο ]
5
⎡
= 0.0833 ⎢
⎣
sq ft
⟨ 2⟩ ⎞
⎟ + ⟨ 6⟩
⟨3⟩ ⎟⎠
⎛ ⟨ 2⟩
⎜⎜
⎝ ⟨3⟩
in. [mm]
⎞⎤
− 1⎟⎟⎥
⎠⎦
⎡
⎤
⟨ 2⟩
⟨ 2⟩
⎢L e = 0.001 [⟨5⟩ ⟨3⟩ ) + ⟨ 6⟩ ( ⟨3⟩ − 1)]⎥
⎣
⎦
in.
[mm]
ft
[m]
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
WATER
COILS
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
GENERAL
CATEGORY
TEST RUN NUMBER
DIMENSIONS
8
8
tw1
- Entering Water Temperature
F
[ΕC]
-
9
9
tw2
- Leaving Water Temperature
F
[ΕC]
-
10
10
twm - Mean Water Temperature
F
[ΕC]
8
-
11
tvm - Mean Steam Temperature
F
[ΕC]
-
11
12
ww - Water Flow Rate
lb per hr
[g/s]
9
-
13
ww - Steam Flow Rate
lb per hr
[g/s]
10
-
14
vvm - Average Saturated Steam Specific Volume
cu ft per lb
[m3/Kg]
-
12
15
(∆pw)T
ft of water
LABORATORY TEST OBSERVATION AND
CALCULATIONS FROM ASHRAE STANDARD
33-78 FORMS 33TD-2 AND 33TD-3
-
- Water Pressure Drop Across Coil at Test
Conditions
[KPa]
-
16
∆pv - Steam Pressure Drop in Coil
-
13
17
Vw - Average Standard Water Velocity Inside
12
-
CALCUALTION AND
PLOTTING
11
Tubes =
18
⟨12⟩
224,500 x ⟨ 4⟩
⎤
⎡
⟨12⟩
⎥
⎢Vw =
1,000,000 x ⟨ 4⟩ ⎦
⎣
wv/Nc- Steam Flow Rate Inside Tubes
= ν13ο/ν3ο
psi
[KPa]
ft per sec
[m/s]
lb per (hr)
(circuit)
[ (gram) per
(second)
(circuit)]
1
2
3
4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
13
WATER
COILS
14
ITEM NO.
STEAM
COILS
GENERAL
CATEGORY
TEST RUN NUMBER
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
19
∆Ph (for Water Coils); ∆ph/vvm (for Steam Coils) - Header,
Nozzles and Tube Entrance and Exit Losses – to be established
by manufacturer
1
2
3
4
--
-
-
-
-
--
-
-
-
-
DIMENSIONS
ft [KPa]
(for water)
(lb)2
(In.)2 (ft)3
⎡
(g ) 2
⎢
⎢ (mm ) 2 (m ) 3
⎣
⎤
⎥
⎥
⎦
-
14
15
-
CALCULATION AND PLOTTING
(for steam)
- Temperature Coorection Factor for tube Circuit
Tube Circuit Water Pressure Drop (From Fig. 7
with ν10ο)
20
Ft
21
∆pt/LeFt - Water Pressure Drop Inside Tubes
=
22
⟨15⟩ − ⟨19⟩
⟨7⟩ x ⟨ 20⟩
− WaterCoils
∆ptv/Levvm - Pressure Drop Parameter for Steam Flow
Inside Tubes
= [ν16ο / (ν7ο x ν14ο)] - ν19ο / ν7ο
ft water per
ft equiv.
tube length
[KPa/m]
(lb ) 2
(in.) 2 (ft ) 4
⎡
⎤
(g ) 2
⎢
⎥
⎢ (mm ) 2 (m ) 4 ⎥
⎣
⎦
-
17
23
15
-
24
Plot ∆pt/LeFt vs Vw (ν21ο vs ν17ο) on logarithmic
coordinates as shown in Fig. 4. This curve with Fig. 7
is sued for application ratings for either cold water or hot
water coils.
Plot Δ∆ptv/Levvm vs wv/Nc (ν22ο vs ν18ο) on logarithmic
coordinates as shown in Fig. 3. This curve is used in
obtaining steam coil application ratings.
CALCULATION OF REFRIGERANT-SIDE THEREMAL RESISTANCES FROM VOLATILE REFRIGERANT COIL TESTS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY ____________________________________________________________________
COIL LINE _______________________________
COIL TYPE _____________________________
NUMERICAL VALUES
1
1
1
2
2
2
3
3
4
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WETTED
SURFACE
GENERAL
CATEGORY
COIL SURFACE _____________________________________________________________________
DRY
SURFACE
SOLUTION
PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
DATE _______________________________
DIMENSIONS
Ao
- Total External Coil Surface
(From Form 410-1)
sq ft
[m2]
DI
- Tube Inside Diameter (From Form 410-1)
in.
[mm]
3
Nt
- Total Number of Tubes in Coil
4
4
Lt
- Coil Finned Tube Length Exposed to Air Flow
5
5
5
B
- Surface Ration (From Form 410-1)
--
6
6
6
Nc
- Number of Tube Circuits in Coil
--
7
7
7
Aix
- Total Cross-Section Fluid Flow Area
Inside Tubes = 0.00545 (ν2ο) 2 x ν6ο
-in.
[mm]
sq ft
[m2]
[Aix = 7.85 x 10-7 (ν2ο) 2 x ν6ο)
8
8
8
Lx
- Straight Tube Length Per Pass
in.
[mm]
9
9
9
Le
- Equivalent Length of Coil Circuit Per Return
Bend
in.
[mm]
Sheet 1 of 11
Form 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
11
11
12
12
13
13
14
14
15
15
16
16
17
17
18
18
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
10
COIL PHYSICAL DATA
FULLY
WETTED
SURFACE
10
LABORATORY TEST OBSERVATIONS AND CALCULATIONS
OBTAINED FROM ASHRAE STANDARD 33-78, FORMS 33TD-1
AND 33TD-4
DRY
SURFACE
TEST RUN NUMBER
10
Le
- Total Equivalent Length of Coil Circuit
⎡⎛ ⟨3⟩ ⎞
⎞⎤
⎛ ⟨3⟩
⎟⎟ + ⟨9⟩ ⎜⎜
− ⟨1⟩ ⎟⎟⎥
= 0.0833 ⎢⎜⎜ ⟨8⟩
⎠⎦
⎝ ⟨ 6⟩
⎣⎝ ⟨ 6⟩ ⎠
DIMENSIONS
ft
[m]
⎡
⎡⎛
⎞⎤ ⎤
⎛ ⟨3⟩
⟨3⟩ ⎞
⎟ + ⟨9⟩ ⎜⎜
− ⟨1⟩ ⎟⎟⎥ ⎥
⎢L e = 0.001 ⎢⎜⎜ ⟨8⟩
⎟
⟨ 6⟩ ⎠
⎠⎦ ⎥⎦
⎝ ⟨ 6⟩
⎢⎣
⎣⎝
11
Ps
- Average Absolute Static Pressure at Test Coil
in. Hg abs
[KPa abs]
12
tl
- Entering Air Dry-Bulb Temperature
F
[ΕC]
13
t 'l
- Entering Air Wet-Bulb Temperature
F
[ΕC]
14
hi
- Entering Air Enthalpy
15
t2
- Leaving Air Dry-Bulb Temperature
16
h2
- Leaving Air Enthalpy
Btu per lb
dry aid
[KJ/Kg]
17
Va
- Standard Air Face Velocity
ft per min
[m/s]
18
Prc2 - Absolute Refrigerant Pressure Leaving Coil
Circuits
Btu per lb
dry air
[KJ/Kg]
F
[ΕC]
psia
[KPa abs]
1
2
3
4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
19
20
20
21
21
22
22
23
23
24
24
25
26
28
DIMENSIONS
)prc -
20
tr1
- Saturated Refrigerant Temperature Entering
Coil Circuits
F
[ΕC]
21
t 'rc 2 - Saturated Refrigerant Temperature Leaving
Coil Circuits
F
[ΕC]
22
trc2 - Temperature of Superheated Refrigerant Leaving
Coil Circuits = tr2
F
[ΕC]
23
wr
- Refrigerant Flow Rate
24
qs
- Average Sensible Cooling Capacity
Btuh
[W]
25
25
qt
- Average Total Cooling and Dehumidifying
Capacity
Btuh
[W]
26
26
qs/qt - Sensible Heat Ratio = ν24ο / ν25ο
(If ν26ο << 0.95, coil surface is all wet or partically
27
28
LABORATORY TEST OBSERVATIONS
AND CALCUALTIONS OBTAINED
FROM ASHRAE STANDARD 33-78,
FORMS 33TD-1 AND 33TD-4
19
CALCULATIONS OF REFRIGEANTSIDE THERMAL RESISTANCES
27
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WETTED
SURFACE
19
GENERAL
CATEGORY
DRY
SURFACE
TEST RUN NUMBER
Refrigerant Pressure Drop Through
Coil Circuits
psi
[KPa]
lb per hr
[g/s]
--
dry; if ν26ο ≧≥ 0.95 coil surface is fully dry)
27
vrc2 - Specific Volume of Saturated Refrigerant Leaving
Coil Circuit (From Refrigerant Tables with ν18ο)
cu ft
per lb
[m3/Kg]
28
RaD + RmD - Combined Air Film Plus Metal Thermal
Resistance (From Fig. 4 with ν17ο )
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
1
2
3
4
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
30
--
31
--
32
--
33
--
34
28
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
--
GENERAL
CATEGORY
FULLY
WETTED
SURFACE
29
29
CALCULATIONS OF REFRIGERANT-SIDE THERMAL RESISTANCES
DRY
SURFACE
TEST RUN NUMBER
∆tm -
Overall Logarithmic Mean Temperature
Difference
DIMENSIONS
1
2
3
4
F
[ΕC]
= (⟨12⟩ − ⟨ 20⟩ ) − (⟨15⟩ − ⟨ 21⟩ )
⎡ ⟨12⟩ − ⟨ 20⟩ ⎤
1n ⎢
⎥
⎣ ⟨15⟩ − ⟨ 21⟩ ⎦
If other than thermal counterflow, determine
the logarithm mean temperature difference
from Figs. 13, 14 or 15.
30
R
- Overall Thermal Resistance = ν1ο x ν29ο
ν25ο
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
31
Rr
- Film Thermal Resistance of Refrigerant
= ν30ο - ν28ο
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
32
fr
- Refrigerant-Side Film Heat Transfer
Coefficient = ν5ο / ν31ο
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
33
qt/Nc - Refrigerant Loading Rate Per Tube
Circuit = ν25ο / ν6ο
Btuh per
circuit
[watt per
circuit]
34
)prc/Levrc2 - Pressure Drop Parameter for Volatile
Refrigerant
(lb ) 2
(in.) 2 (ft ) 4
=
ν19 ο
ν10ο x ν27ο
⎡
⎤
(g ) 2
⎢
2
4⎥
⎣⎢ (mm) (m) ⎦⎥
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
29
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WETTED
SURFACE
35
GENERAL
CATEGORY
DRY
SURFACE
TEST RUN NUMBER
35
wr/Nc - Volatile Refrigerant Flow Rate Per
36
-
37
30
-
31
-
-
-
32
33
34
CALCULATIONS OF REFRIGERANT-SIDE THERMAL RESISTANCES
Tube Circuit = ν23ο / ν6ο
1
2
3
4
--
-
-
-
-
--
-
-
-
-
DIMENSIONS
lb per hr
per circuit
⎡gram per ⎤
⎢sec ond per ⎥
⎥⎦
⎢⎣circuit
36
Plot Rr vs qt/Nc (ν31ο vs ν33ο) on logarithmic coordinates
as shown in Fig. 6.
37
Plot Δpc/Levrc2 vs wr/Nc (ν34ο vs ν35ο) on logarithmic
coordinates as shown in Fig. 6. This curve is used for
application ratings of volatile refrigerant coils.
38
RaW
- Air Film Thermal Resistance for Wet Surface
(From Fig. 5 with ν17ο)
39
fr (Assumed) - Refrigerant-Side Film Heat Surface
Transfer Coefficient
Note:
40
Rr
Assume this value for trial and
error solution. Suggest initial
trial value of 300.
- Film Thermal Resistance of Refrigerant
= ν5ο / ν39ο
41
RmW - Approximate Total Metal Thermal Resistance
(Wetted Surface) (From Fig. 2 with faW = 1/ν38ο)
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
(hr) (sq ft)
(F) per Btu
[m2 Α Εc/w]
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
-
36
-
37
-
38
-
39
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
35
GENERAL
CATEGORY
FULLY
WETTED
SURFACE
-
42
CALCULATIONS OF REFRIGERANT-SIDE THERMAL
RESISTANCES
DRY
SURFACE
TEST RUN NUMBER
C Δ- Approximate Coil Characteristic (for Wetted Surface)
⎡
⟨ 40⟩ + ⟨ 41⟩
⟨ 40⟩ + ⟨ 41⟩ ⎤
=
⎢C =
⎥
0.243 ⟨38⟩ ⎣
1.018 ⟨38⟩ ⎦
Note:
This approximate value of C is used
only to obtain the final value of RmW
in ν48ο.
DIMENSIONS
4
⎡ Kg ⋅ °C ⎤
⎢ KJ ⎥
⎣
⎦
- Mean Air Enthalpy = 0.5 (ν14ο + ν16ο)
44
trm
- Mean Refrigerant Temperature
= 0.5 (ν20ο + ν21ο)
F
[ΕC]
45
tsm
- Approximate Mean Surface Temperature
F
[ΕC]
m " / c p -Approximate Air-Side Heat Transfer Multiplier
3
per Btu
hm
46
2
(lb) (F)
43
(From Fig. 9 with ν42ο, ν43ο, and ν44ο)
1
Btu per lb
dry air
[KJ/Kg
--
for Wet Surface Coils
(From Fig. 8 with ν11ο and ν45ο)
- Air-Side Heat Transfer Coefficient = ν46ο / ν38ο
-
40
47
faW
-
41
48
RmW - Total Metal Thermal Resistance of Fin and Tube
for Wet Surface (From Fig .2 with 47)
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
((hr) (sq ft)
(F) per Btu
[m2 Α ΕC]
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
-
43
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
42
GENERAL
CATEGORY
FULLY
WETTED
SURFACE
-
49
CALCULATIONS OF REFRIGERANT-SIDE THERMAL RESISTANCES
DRY
SURFACE
TEST RUN NUMBER
C
- Coil Charactertistic for Wetted Surface
=
50
t "l
⎡
⟨ 40⟩ + ⟨ 48⟩ ⎤
⎢C =
⎥
1
.018 ⟨38⟩ ⎦
⎣
⟨ 40⟩ + ⟨ 48⟩
0.243 ⟨38⟩
- Entering Air Dew Point Temperature
(From Psychrometric Chart with ν11ο , ν12ο,
and ν13ο)
DIMENSIONS
1
2
3
4
(lb) (F)
per Btu
⎡ Kg ⋅ °C ⎤
⎢ KJ ⎥
⎣
⎦
F
[ΕC]
Calculation of Dew Point Temperature for
Nonstandard Air Pressure*
⎡ (p − p' ) ( t l − t 'l ) ⎤
p v = p' − ⎢ s
⎥
'
⎣⎢ 2830 − 1.44 t l ⎦⎥
(
)(
⎡
⎛ p − p ' t l − t 'l
⎢p v = p ' − ⎜ s
⎜ 1548.4 − 1.33 t '
⎢⎣
l
⎝
)⎞⎟⎤⎥
⎟⎥
⎠⎦
Where: ps = Air Pressure---------------
p ' = Saturation Vapor
Pressure at t 'l
from Steam
Tables------------------
in. Hg abs
{Kpa abs]
pv = Saturation Vapor
Pressure at Dew
Point Temperature---
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
-
44
45
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
CALCULATIONS OF REFRIGERANT-SIDE THERMAL RESISTANCES
-
FULLY
WETTED
SURFACE
DRY
SURFACE
TEST RUN NUMBER
t "l = Dew Point Temperature
Is Saturation Temperature Corresponding to Saturation
Vapor Pressure, pv
from Steam Tables -51
tsl
-
Coil Suface Temperature on Entering Air
Side (From Fig. 9 with ν14ο, ν20ο, and
ν49ο unless ν11ο varies more than ∀0.3
in. Hg [∀1.014 KPa] from 29.92 in Hg.
[101.325 Kpa]. If it does, then determine
tsl by trial and error using equation:
DIMENSIONS
F
[ΕC]
F
[ΕC]
tsl = trl + C (hl - hsl).
Correct hsl for ν11ο and use ν14ο, ν20ο,
and ν49ο.
For fully wetted coil ν50ο ≧ ν51ο.
If ν50ο < ν51ο, coil is partially wet and
calculation procedures may be determined
from Form 410-6)
52
hsl
- Saturated Air Enthalpy at tsl (From Air Enthalpy
Tables with ν11ο and ν51ο)
Btu per lb
dry air
[KJ/Kg]
1
2
3
4
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
-
-
-
47
48
49
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
46
GENERAL
CATEGORY
FULLY
WETTED
SURFACE
-
53
CALCULATIONS OF REFRIGERANT-SIDE THERMAL
RESISTANCES
DRY
SURFACE
TEST RUN NUMBER
ts2
- Coil Surface Temperature on Leaving Air Side
(From Fig. 9 with ν16ο, ν21ο, and ν49ο unless
ν11ο varies more than ∀0.3 in. Hg [∀1.014 Kpa]
from 29.92 in. Hg [101.325 Kpa]. If it does, then
determine ts2 by trial and error using equation:
DIMENSIONS
1
2
3
4
F
[ΕC]
ts2 = tr2 +C (h2 - hs2).
Correct hs2 for ν11ο and use ν16ο, ν21ο, and ν49ο.)
54
hs2
- Saturated Air Enthalpy at ts2 (From Air Enthalpy
Tables with ν11ο and ν53ο)
Btu per lb
dry air
[KJ/Kg]
55
∆hm - Logarithmic Mean Enthalpy Difference
=
56
Ac
(⟨14⟩ − ⟨52⟩ )
⎡ ⟨14⟩
ln ⎢
⎣ ⟨16⟩
− (⟨16⟩ − ⟨54⟩ )
−
−
⟨52⟩ ⎤
⎥
⟨54⟩ ⎦
- Calculated External Surface Area of Coil
= 0.243 (ν38ο x ν25ο/ν55ο)
Btu per lb
dry air
[KJ/Kg]
sq ft
[m2]
[Ac = 1.018 (ν38ο x ν25ο / ν55ο)]
FORM 410-4
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
GENERAL PROCEDURE
NUMERICAL VALUES
50
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WETTED
SURFACE
-
GENERAL
CATEGORY
DRY
SURFACE
TEST RUN NUMBER
Assume other values for ν39ο and repeat procedure
57
DIMENSIONS
--
1
2
3
4
-
-
-
-
-
-
-
-
through ν56ο. Plot ν39ο vs ν56ο as in Fig. 12b.
Two or more points should be plotted so that Ao
lies between calculated values of Ac.
-
51
58
fr
- Refrigerant Side Film Heat Transfer Coefficient
Note: The point on the curve (Fig. 12b), as
PLOTS
plotted in ν57ο, where Ac = Ao
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
determines the value of fr corresponding
to the circuit loading, ν33ο.
-
52
59
-
53
60
Rr
- Film Thermal Resistance of Refrigerant = ν5ο/ν58ο
Plot Rr vs qt/Nc (ν59ο vs ν33ο) on logarithmic
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
--
coordinates as shown in Fig. 6. This curve
is used to obtain application rating data.
SIGNED __________________________________________________________ TITLE _________________________________________________________
t l' h l
t sl' h sl
t 2' h 2
t rl
t s 2' h s 2
t rc 2
Form 410- 9
SUGGESTED FORM FOR RATING CALCULATION PROCEDURE FOR SENSIBLE HEAT AIR COILS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY ____________________________________________________________________
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
DATE _______________________________
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
TO SOLVE FOR
CAPACITY (qs)
GENERAL
CATEGORY
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
STEAM
COILS
HOT OR
COLD
WATER
COILS
1
1
1
1
1
2
2
2
2
2
3
3
3
3
4
4
4
4
5
5
5
5
6
6
6
6
7
7
7
7
8
8
8
9
9
9
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
DIMENSIONS
- Coil Face Height
in.
[mm]
L
- Coil Face Length
in.
[mm]
3
Af
- Coil Face Area
4
B
- Surface Ration (From Form 410-1)
--
5
Nr
- Number of Rows Deep
--
6
Nt
- Total Number of Tubes in Coil
--
7
Nc
- Parallel Tube Circuits in Coil
--
8
8
Ao/AfNr
9
9
Ao
COIL PHYSICAL DATA
H
= ν8ο x ν3ο x ν5ο
sq ft
[m2]
(sq ft ) per
(sq ft – F.A.)
(row)
sq ft
Form 410- 9
10
10
10
10
10
Di
- Tube Inside Diameter
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
in.
[mm]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
TO SOLVE FOR
CAPACITY (qs)
STEAM
COILS
HOT OR
COLD
WATER
COILS
11
11
11
11
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
11
Aix
- Total Cross Sectional Fluid Flow Area
Inside Tubes = 0.00545 (ν10ο2 x ν7ο)
DIMENSIONS
sq ft
[m2]
12
12
12
12
13
13
13
13
14
14
14
14
COIL PHYSICAL DATA
[Aix = 7.85 x 10-7 (ν10ο x ν7ο)]
12
Ls
- Straight Tube Length Per Tube Pass
13
Kb
- Equivalent Length of Coil Circuit Per Return Bend
14
Le
- Total Equivalent Length of Coil Circuit
⎡⎛
6⎞
⎛6
⎞⎤
= 0.0833 ⎢⎜ ⟨12⟩ ⎟ + ⟨13⟩ ⎜ − 1⎟⎥
7⎠
⎝7
⎠⎦
⎣⎝
15
15
15
15
NG
CON
DITI
⎡
⎢L e = 0.001
⎣
15
Qa
in.
[mm]
in.
[mm]
ft
[m]
⎛⎛
7⎞
⎛ 6 ⎞ ⎞⎤
⎜⎜ ⎜ ⟨12⟩ ⎟ + ⟨13⟩ ⎜ − 1⎟ ⎟⎟⎥
7⎠
⎝ 7 ⎠ ⎠⎦
⎝⎝
- Air Volume Flow at Standard Conditions
scfm
[std Ρ/s]
Form 410- 9
16
16
16
16
16
Va
- Standard Air Face Velocity, ν15ο/ν3ο
Va = 0.001 x ν15ο/ν3ο]
17
17
17
17
17
tl
- Entering Air Dry-Bulb Temperature
-
18
-
18
18
Vw
- Average Standard Water Velocity in Tubes
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
ft per min
[m/s]
F
[ΕC]
ft per sec
[m/s
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
19
-
19
18
20
18
20
19
-
19
-
20
-
20
-
21
-
21
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
-
19
COIL PHYSICAL DATA
STEAM
COILS
HOT OR
COLD
WATER
COILS
M
PROP
ERTIE
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
S
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
DIMENSIONS
F
[ΕC]
Twl
- Entering Water Temperature
Ps
- Average Absolute Static Pressure at Coil
21
Pv1
- Inlet Steam Gage Pressure to Coil
22
t 'vl
- Inlet Steam Temperature to Coil
F
[ΕC]
23
Pvl
- Coil Inlet Steam Pressure
psia
20
= ν21ο + 0.491 ν20ο [Pvl = ν21ο + ν20ο]
in. Hg abs
[Kpa abs]
psig
[Kpa gage]
[Kpa abs)
Form 410- 9
22
-
22
-
24
tvl
- Steam Saturation Temperature Entering Coil
(From ν23ο and Steam Property Tables)
23
-
23
-
25
vvl
- Steam Specific Volume Entering Coil
(From ν22ο, ν23ο and Steam Property Tables)
= vv2 for rating convenience
24
-
24
-
26
hvl
- Enthalpy of Steam Entering Coil
(From ν22ο, ν23ο and Steam Property Tables)
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
F
[ΕC]
cu ft per lb
[m3/Kg]
Btu per lb
[KJ/Kg]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
-
25
-
21
-
21
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
25
GENERAL
CATEGORY
STEAM
COILS
HOT OR
COLD
WATER
COILS
STEAM
PROPERTIES
STEAM
COILS
HOT OR
COLD
WATER
COILS
-
NUMERICAL
VALUES
TO SOLVE FOR
CAPACITY (qs)
27
WATER RATING
PARAMETERS
TO SOLVE FOR
ROWS DEEP (Nr)
28
hf2
- Enthalpy of Steam Condensed Leaving Coil
(From ν23ο and Steam Property Tables as-
DIMENSIONS
Btu per lb
[KJ/Kg]
suming hfl = hf2 for rating convenience)
twm
- Mean Water Temperature Inside Tubes
-
When solving for rows deep, this value is
known (assume cpw = 1.000 for this calculation)
-
When solving for capacity, this value must
be approximated (Suggest twm be 5 F [2.8ΕC
to 10 F [5.6ΕC] from twl
F
[ΕC]
Form 410- 9
-
22
-
22
29
ww
- Water Flow Rate = 224,500 x ν11ο x ν18ο
[ww = 1,000,000 x ν11ο x ν18ο]
-
23
-
23
lb per hr
[g/s]
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
-
24
-
24
-
25
-
25
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
31
WATER RATING
PARAMETERS
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
DIMENSIONS
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
32
RaD + RmD - Combined Air Film Plus Metal Thermal
Resistance (From Fig. 4 with ν16ο
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
Form 410- 9
26
26
26
26
33
R
- Overall Thermal Resistance between Air – and
Tube-Side Fluid = ν31ο + ν32ο for Water
Coils (From Fig. 3 knowing ν16ο for Steam
Coils)
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
-
-
27
27
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
C CU
O
NS TO SOLVE
FOR COIL
CAPACITY
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
34
M
- Air-to-Tube Fluid-Side Heat Capacity Ratio
=
4.5 x ⟨15⟩ x c p
⟨ 29⟩
DIMENSIONS
--
1.2 x ⟨15⟩ x c p ⎤
⎡
⎢M =
⎥
⟨ 29⟩
⎣
⎦
Form 410- 9
-
-
28
28
35
Co
- Heat Transfer Exponent
=
-
-
29
29
36
E
⟨9⟩
4.5 c p x ⟨15⟩ x ⟨33⟩
--
⎤
⎡
⟨9⟩
⎥
⎢C o =
1.2c p x ⟨15⟩ x ⟨33⟩ ⎥⎦
⎢⎣
--
- Air-Side Effectiveness
- at ν34ο and ν35ο = 0 and Fig. 13 for
Steam Coils
- at ν34ο, ν35ο, and Fig. 13 for One-Row
Water Coils
- at ν34ο, ν35ο, and Fig. 14 for Two-Row
Water Coils
- at 34, 35, and Fig. 15 for Three-Row or
Greater Counterflow Water Coils
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
NUMERICAL
VALUES
TO SOLVE FOR
CAPACITY (qs)
GENERAL
CATEGORY
TO SOLVE FOR
ROWS DEEP (Nr)
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
-
-
-
-
27
-
-
-
-
30
31
32
33
33
30
31
32
34
34
37
CALCULATIONS TO SOLVE FOR COIL CAPACITY (qs)
27
Δto
- Initial Air-to-Field Temperature Difference
= ν19ο - ν17ο - For Air-Heating Water Coils
= ν17ο - ν19ο - For Air-Cooling Water Coils
[ΕC]
= ν24ο - ν17ο - For Steam Coils
38
qs
- Coil Sensible Heat
Btuh
= 4.5 cp x ν15ο x ν36ο x ν37ο
[ qs = 1.2 cp x ν15ο x ν36ο x ν37ο ]
39
)ta
- Air Temperature Rise or Drop Across Coil
=
40
t2
38
4.5 c p x ⟨15⟩
⎡
⎤
38
⎢Δt a =
⎥
1.2 c p x ⟨15⟩ ⎦⎥
⎣⎢
- Leaving Air Temperature at Coil
= ν17ο + ν39ο (For Air Heating)
= ν17ο - ν39ο (For Air Cooling)
41
)tw
- Water Temperature Rise or Drop Across Coil
= ν18ο / ν29ο
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
F
[W]
F
[ΕC]
F
[ΕC]
F
[ΕC]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
TO SOLVE FOR
CAPACITY (qs)
CATEG
ITEM
NO.
TO SOLVE FOR
ROWS DEEP (Nr)
GENER
AL
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
STEAM
COILS
HOT OR
COLD
WATER
COILS
STEAM
COILS
HOT OR
COLD
WATER
COILS
-
-
-
35
42
*twm - Average Water Temperature Inside Tubes
= ν19ο - 0.5 x ν41ο - For Air-Heating Coil
28
29
30
-
-
28
29
30
31
32
-
-
-
-
-
-
-
-
-
-
CALCULATIONS TO SOLVE FOR ROWS DEEP
= ν19ο + 0.5 x ν41ο - For Air-Cooling Coil
43
qs
- Coil Sensible Heat (Known)
F
[ΕC]
Btuh
[W]
44
)ta
- Air Temperature Rise or Drop Across Coil
=
45
t2
43
4.5 c p x ⟨15⟩
⎡
⎤
43
⎢Δt a =
⎥
1.2 c p x ⟨15⟩ ⎥⎦
⎢⎣
- Leaving Air Temperature at Coil
= ν17ο + ν44ο For Air-Heating Coil
= ν17ο - ν44ο For Air-Cooling Coil
46
)tw
- Water Temperature Rise or Drop Across Coil
= ν43ο / ν29ο
47
tw2
F
[ΕC]
F
[ΕC]
F
[ΕC]
- Leaving Water Temperature at Coil
= ν19ο - ν46ο - For Air-Heating Coil
= ν19ο + ν46ο - For Air-Cooling Coil
F
[ΕC]
* ν42ο must equal ν28ο within ∀5 F [∀2.8]. If not, assume a new value for ν28ο and repeat calclations through ν42ο.
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL LINE _______________________________
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
Form 410- 9
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
31
33
-
-
32
33
34
35
34
35
36
37
-
-
-
-
-
-
-
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
48
CALCULATIONS TO SOLVE FOR ROWS DEEP
TO SOLVE FOR
ROWS DEEP (Nr)
M
- Air-to-Tube Fluid-Side Heat Capacity Ratio
DIMENSIONS
--
= ν46ο / ν44ο - For Water Coils
= 0 - For Steam Coils (for rating convenience)
49
E
- Air-Side Effectiveness
--
= ν44ο / ν37ο
50
51
Co
Nrc
- Heat Transfer Exponenet (Air-to-Tube Fluid)
-
From Fig. 13 or 14 or 15 with ν48ο and ν49ο
-
Fig. 13 for One-Row Coils
-
Fig. 14 for Two-Row Coils
-
Fig. 15 for Coils with three rows or more
- Calculated Row Depth Required
=
52
Nt
⟨ 43⟩
⟨8⟩
--
--
x ⟨33⟩ x ⟨50⟩
x ⟨3⟩ x ⟨ 44⟩
- Integral Coil Row Depth Installed
--
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
36
38
34
36
37
38
39
39
40
-
35
36
37
37
38
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
53
CALCULATIONS TO SOLVE FOR ROWS DEEP
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
)pst/Nr - Air-Side Pressure Drop Per Row Deep at
Standard Conditions (From Fig. 3 or 4
with ν16ο)
DIMENSIONS
in. water
row
[pascal per
row]
54
Fa
- Air-Side Pressure Drop Correction Factor
--
⎡ ⟨17⟩ + ⟨ 40⟩ + ⟨ 45⟩ ⎤
460 + ⎢
⎥
2
⎣
⎦
=
17.71 x ⟨ 20⟩
⎡
⎛ ⟨17⟩ + ⟨ 40⟩ or ⟨ 45⟩ ⎞ ⎤
273.15 + ⎜
⎟⎥
⎢
2
⎝
⎠⎥
⎢Fa =
2.909 x ⟨ 20⟩
⎢
⎥
⎢
⎥
⎣
⎦
55
56
()pa)JOB - Air-Side Pressure Pressure Drop at Job Conditions
wv
in water
(Constant wa) = ν52ο x ν53ο x ν54ο
[Pa]
- Total Steam Condensate Mass Flow Rate Through
lb per hr
Coil = ν38ο or ν43ο
ν26ο or ν27ο
[g/s]
Form 410- 9
40
-
38
-
57
wv/Nc - Steam Flow Rate Per Tube Circuit
= ν56ο / ν7ο
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
lb per (hr)
(circuit)
[(gram) per second) (circuit)
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
41
41
39
39
-
42
43
-
-
40
41
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
STEAM
COILS
HOT OR
COLD
WATER
COILS
-
NUMERICAL
VALUES
TO SOLVE FOR
CAPACITY (qs)
58
CALCULATIONS TO SOLVE FOR ROWS DEEP
TO SOLVE FOR
ROWS DEEP (Nr)
Obtain Header, Nozzle and Entrance and Exit Losses for
Water and Steam to be determined by manufacturer
)ph/Fh - for Water Coils at 60ΕF Mean Water
Temperature with ν18ο
)ph/vvm - for Steam Coils
59
60
)pt/LeFt
Fh
- Tube Circuit Water Pressure Drop Parameter
at 60 F [15.6ΕC] Mean Water Temperature
(From Fig. 4 with ν18ο ) (Ft = l)
- Temperature Correction Factor for Header Water
Pressure Drop (From Fig. 7 with ν28ο
DIMENSIONS
ft of water
[kPa]
(lb)2
(in.)2 (ft)3
⎡
⎤
(g ) 2
⎢
2
3⎥
⎣⎢ (mm) (m) ⎦⎥
ft water
per ft
[KPa/m]
--
Form 410- 9
-
44
-
42
61
Ft
-
45
-
43
62
)pw)JOB - Water Pressure Drop Across Coil at Job Conditions
- Temperature Correction Factor for Water Pressure
Drop (From Fig. 7 with ν28ο )
= ν58ο x ν60ο + ν14ο x ν59ο x ν61ο
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
--
ft water
[Kpa]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
STEAM
COILS
HOT OR
COLD
WATER
COILS
42
-
40
-
43
-
41
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
STEAM
COILS
HOT OR
COLD
WATER
COILS
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY (qs)
63
TUBE-SIDE PRESSURE
DROP CALCULATIONS
TO SOLVE FOR
ROWS DEEP (Nr)
NUMERICAL
VALUES
)ptv/Lcvvm - Steam Pressure Drop Parameter
(From Fig. 3 with ν57ο
DIMENSIONS
(lb)2
(in.)2 (ft)4
⎡
⎤
(g ) 2
⎢
2
4⎥
⎣⎢ (mm) (m) ⎦⎥
64
)pv
- Steam Pressure Drop Inside Tubes at Job Conditions
= [(ν63ο x ν14ο) + ν58ο ] ν25ο
psi
[Kpa]
Form 410- 9
Signed ____________________________________________________________________ Title
____________________________________________________________________
SUGGESTED FORM FOR RATING CALCULATION PROCEDURE FOR COOLING AND DEHUMIDIFYING COILS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
1
1
2
2
2
2
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
1
GENERAL
CATEGORY
FULLY
WET
SURFACE
1
COIL
PHYSICAL
DATA
STEAM
COILS
VOLATILE
REFRIGERANT
COILS
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
COLD WATER
COILS
DIMENSIONS
1
H
- Coil Face Height
in.
[mm]
2
L
- Coil Face Length
in.
[mm]
Form 410- 9
3
3
3
3
3
Af
- Coil Face Area
4
4
4
4
4
B
- Surface Ration (From Form 410-1)
--
5
5
5
5
5
Nr
- Number of Rows Deep (if known)
--
6
6
6
6
6
Nt
- Total Number of Tubes in Coil (if known)
--
7
7
7
7
7
Nc
- Parallel tube Circuits in Coil (if known)
--
8
8
8
8
8
Ao/AfNr
sq ft
[m2]
(sq ft) per
(sq ft – F.A.)
(row)
[(sq metre) per]
[(sq metre-F.A.)
(Row)
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
9
9
9
9
10
10
10
10
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
GENERAL
CATEGORY
COIL
PHYSICAL
DATA
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
STEAM
COILS
FULLY
WET
SURFACE
PARTICLALY
WET
SURFACE
COLD WATER
COILS
DIMENSIONS
9
Di
- Tube Inside Diameter
in.
[mm]
10
Ls
- Straight Tube Length Per Tube Pass
in.
[mm]
Form 410- 9
11
11
11
11
Kb
- Equivalent Length of Coil Circuit Per Return Bend
in.
[mm]
12
12
12
12
12
Ao
- ν8ο x ν3ο x ν5ο (if known)
sq ft
[m2]
13
13
13
13
13
Aix
- Total Cross-Sectional Fluid Flow Area
sq ft
[m2]
14
14
14
14
15
15
15
15
16
16
16
16
RATING CONDITIONS AND DATA COMUPATTIONS
11
Inside Tubes = 0.00545 (ν92ο x ν7ο)
[Aix = 7.85 x 10-7 (ν9ο2 x ν7ο)]
14
Le
Total Equivalent Length of Coil Circuit
⎡⎛
⟨6⟩ ⎞
⎟ + ⟨11⟩
= 0.0833⎢⎜⎜ ⟨10⟩
⟨7⟩ ⎟⎠
⎣⎝
⎡
⎢L e = 0.001
⎣⎢
⎛ ⟨6⟩
⎞⎤
⎜⎜
− l ⎟⎟⎥
⎝ ⟨ 7⟩
⎠⎦
[m]
⎛⎛
⎛ ⟨6⟩
⎞ ⎞⎤
⟨6⟩ ⎞
⎜ ⎜⎜ ⟨10⟩
⎟⎟ + ⟨11⟩ ⎜⎜
− 1⎟⎟ ⎟⎟⎥
⎜
⟨ 7⟩ ⎠
⎝ ⟨7⟩
⎠ ⎠⎦⎥
⎝⎝
15
Qa
- Air Volume Flow at Standard Conditions
scfm
[std Ρ/s]
16
Va
- Standard Air Face Velocity = ν15ο/ν3ο
ft per min
[m/s]
[Va = 0.001 x ν15ο/ν3ο
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
ft
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
ITEM NO.
GENERAL
CATEGORY
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
COLD WATER
COILS
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
17
17
17
17
tl
- Entering Air Dry-Bulb Temperature
F
[ΕC]
18
18
18
18
18
t 'l
- Entering Air Wet-Bulb Temperature
F
[ΕC]
19
19
-
-
19
Vw
- Average Standard Water Velocity in Tubes
20
20
-
-
20
twl
- Entering Water Temperature
F
[ΕC]
-
-
19
19
21
tr2
- Saturated Suction Refrigerant Temperature at Coil
Outlet
F
[ΕC]
-
-
20
20
21
21
21
21
-
-
22
22
RATING CONDITIONS AND DATA COMPUTATIONS
17
Note: For rating convenience, it is assumed that
there is no temperature drop from coil
circuits to coil outlet.
22
t 'r 2
- Superheated Refrigerant Temperature at Coil Outlet
Note: For rating convenience, it is assumed that
there is no temperature drop from coil
circuits to coil outlet.
23
Ps
- Average Absolute Static Pressure at Coil
24
tro
- Refrigerant Temperature Entering the Coil Control
Device (Equal to the refrigerant condensing
temperature)
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
ft per sec
[m/s]
F
[ΕC]
in. Hg abs
[Kpa abs]
F
[ΕC]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
CATEG
ITEM
NO.
COLD WATER
COILS
GENER
AL
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
FULLY
WET
SURFACE
-
23
23
22
22
24
24
23
23
25
25
24
25
24
25
26
27
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
26
27
25
RATING CONDITIONS AND DATA COMPUTATIONS
PARTIALLY
WET
SURFACE
-
hro
- Enthalpy of Refrigerant Entering Coil
Control Device (From ν24ο and Refrigerant Tables)
Btu per lb
[KJ/Kg]
26
hl
- Entering Air Enthalpy
(From ν17ο, ν18ο, and ν23ο)
Btu per lb
[KJ/Kg]
27
60wa - Standard Air Flow Rate = 4.50 x ν15ο
lb per hr
[g/s]
[1000wa = 1.2 x ν15ο ]
28
29
Case I -
If ν29ο is known, determine ν30ο at ν29ο
saturated and ν23ο . Then calculate
ν31ο = ν27ο (ν26ο - ν30ο).
Case II -
If ν31ο is known, determine ν30ο and then ν29ο.
ν30ο = ν26ο – ν31ο/ν27ο.
Case III -
If ν5ο is known, assume ν31ο or ν29ο, find ν30ο
and then ν29ο or ν31ο, respectively.
t '2
- Leaving Air Wet-Bulb Temperature
COIL LINE _______________________________
--
F
[ΕC]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
Form 410- 9
GENERAL PROCEDURE
28
28
27
28
27
28
29
-
29
-
29
29
-
-
-
-
30
30
-
-
31
31
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
26
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
26
30
RATING CONDITIONS AND DATA COMPUTATIONS
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
H2
- Leaving Air Enthalpy
If qt is known, h2 = ν26ο -
31
qt
qt
⟨27⟩
- Total Heat Capacity of Coil
= ν27ο (ν26ο - ν30ο)
DIMENSIONS
Btu per lb
[KJ/Kg]
Btuh
[W]
Enter numerical value if known.
If not known, assume a numberical value
for a trial and error solution.
32
ww
- Water Flow Rate = 224,500 x ν13ο x ν19ο
[ww = 1,000,000 x ν13ο x ν19ο]
lb per hr
[g/s]
33
tw2
- Leaving Water Temperature = ν20ο + ν31ο/ν32ο
34
Pr2
- Absolute Pressure of Refrigerant at Coil Outlet
(From Refrigerant Tables with ν21ο)
psia
[KPa abs]
35
hr2
- Enthalpy of Saturated Refrigerant Vapor at Coil
Outlet Pressure (From Refrigerant Tables with
ν21ο. Assumed saturated for rating convenience.)
Btu per lb
F
[ΕC]
[KJ/Kg]
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
32
-
-
33
33
-
-
34
34
-
35
35
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
32
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
-
RATING CONDITIONS AND DATA COMPUTATIONS
FULLY
WET
SURFACE
-
-
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
36
vr2
- Specific Volume of Saturated Refrigerant Vapor
at Coil Outlet Pressure (From Refrigerant Tables
with ν21ο. Assumed saturated for rating convenience.
- Refrigerant Flow Rate = ν31ο/(ν35ο - ν25ο)
37
wr
38
wr/Nc - Refrigerant Flow Rate Per Tube Circuit
= ν37ο/ ν7ο
DIMENSIONS
cu ft per lb
[m3/Kg]
lb per hr
[g/s]
lb per (hr)
(circuit)
⎡(gram) per ⎤
⎢ (sec ond ) ⎥
⎢⎣ (circuit ) ⎥⎦
39
)prc/Levr2 - Refrigerant Pressure Drop Parameter
(From Fig. 6 with ν38ο)
(lb) 2
(in.) 2 (ft ) 4
⎡
(g )2 ⎤
⎥
⎢
2
4
⎢⎣ (mm) (m ) ⎥⎦
Form 410- 9
-
-
36
36
40
)prh/vr2 - Outlet Header Refrigerant Pressure
Drop Parameter with ν17ο)
(lb)2
(in.) 2 (ft ) 3
⎡
⎤
(g ) 2
⎢
⎥
2
3
⎣⎢ (mm) (m) ⎦⎥
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
37
37
-
-
38
38
-
-
39
39
-
-
40
40
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
-
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
-
RATING CONDITIONS AND DATA
COMPUTATIONS
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
41
pr1
-
Absolute Pressure of Refrigerant at Coil Inlet,
ν34ο + ν36ο [(ν14ο x ν39ο) + ν40ο]
DIMENSIONS
psia
[Kpa abs]
42
prc2
- Absolute Pressure of Refrigerant Leaving Coil
Circuit = ν34ο + ν36ο x ν40ο)
psia
[Kpa abs]
43
trc2
- Saturated Refrigerant Temperature Leaving Coil
Circuit (From ν42ο and Refrigerant Tables)
F
[ΕC]
44
tr1
- Entering Refrigerant Temperature (From
Saturated Refrigerant Tables with ν41ο)
F
[ΕC]
Form 410- 9
-
30
30
41
41
45
qt/Nc - Refrigerant Circuit Loading Rate
= ν31ο/ν7ο
-
-
46
twm
- Mean Water Temperature in Coil
= 0.5 (ν20ο + ν33ο)
31
31
-
-
47
fw
- Water-Side Film Heat Transfer Coefficient
150 (1 + 0.011 ⟨ 46⟩ ) (⟨19⟩ ) 0.8
=
(⟨9⟩ ) 0.2
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
Btu per (hr)
(circuit)
[watt per
circuit]
F
[ΕC]
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
42
33
43
43
ITEM NO.
FULLY
WET
SURFCE
42
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
32
RATING CONDITIONS
AND DATA
COMPUTATIONS
FULLY
WET
SURFACE
32
33
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
48
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
Tube-Side Thermal Resistance
Rw = ν4ο/ν47nο For Water Coils
Rr - From Fig. 6 with ν45ο for Volatile Refrigerant Coils
49
RaD - Air Film Thermal Resistance for Dry Surface
(From Fig. 5 or 6 with ν16ο)
DIMENSIONS
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
Form 410- 9
34
34
44
44
50
RaW - Air Film Thermal Resistance for Wetted Surface
(From Fig. 5 or 6 with ν16ο)
35
35
45
45
51
RmD - Metal Thermal Resistance for Dry Surface
(From Fig. 2 at fa = 1/ν49ο)
36
36
46
46
52
Approximate Coil Charactertistic =
⟨ 48⟩ + ⟨51⟩
0.243 x 50
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
(hr) (sq ft)
(F) per Btu
[m2 Α ΕC/W]
(lb) (F)
per Btu
[Kg Α ΕC/KJ]
⎡ ⟨ 48⟩ + ⟨51⟩ ⎤
⎢=
⎥
⎣ 1.018 x ⟨50⟩ ⎦
Note: This approximate coil characteristic is used to obtain
RmW in ν63ο.
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
47
47
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
37
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
37
53
RATING
PARAMETERS
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
Y
-
Ratio of Tube-Side Temperature Difference to
Air Enthalpy Difference
⟨33⟩ − ⟨ 20⟩
=
− For Water Coils
⟨ 26⟩ − ⟨30⟩
=
DIMENSIONS
(lb) (F)
per Btu
[Kg Α ΕC/KJ]
⟨ 44⟩ − ⟨ 21⟩
− For Volatile Re frigerant Coils
⟨ 26⟩ − ⟨30⟩
Form 410- 9
38
38
48
48
54
tl
- Entering Air Dew Point Temperature (From Psychrometric Chart with ν17ο, ν18ο, and ν23ο)
Calculation of Dew Point Temperature for
Nonstandard Air Pressure*
F
[ΕC]
⎡ (⟨ 23⟩ − p ' ) (⟨17⟩ − ⟨18⟩ ) ⎤
pv = p' − ⎢
⎥
2830 − 1.44 ⟨18⟩
⎢⎣
⎥⎦
⎡
⎡ (⟨ 23⟩ − p ' ) (⟨17⟩ − ⟨18⟩ ) ⎤ ⎤
⎢p v = p ' − ⎢
⎥⎥
⎢⎣
⎢⎣ 1548.4 − 1.33 ⟨18⟩ ⎦⎥ ⎥⎦
⎫
Where : p = Saturation Vapor Pr essure at
⟨18⟩ , from Steam Tables − − − ⎪⎪
⎬
p v = Saturation Vapor Pr essure at
⎪
Dew Po int Temperature − − − − ⎪⎭
t "l
[Kpa abs]
= Dew Point Temperature is Saturation Temperature Corresonding to Saturation Vapor Pressure,
Pv, from Steam Table-------------
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
in. Hg abs
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
49
49
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
39
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
39
G
PARA
METE
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
55
h "l
-
Saturation Enthalpy at Dew Point (From
Psychrometric Charts with ν54ο and ν23ο)
DIMENSIONS
Btu per lb
[KJ/Kg]
Form 410- 9
40
40
50
50
56
Approximate Air Enthalpy at Boundary Conditions
=
⟨54⟩ − ⟨33⟩ + (⟨53⟩ x ⟨ 26⟩ ) + (⟨52⟩ x ⟨55⟩ )
⟨52⟩ + ⟨53⟩
Btu per lb
[KJ/Kg]
For Water Coils
=
⟨54⟩ − ⟨ 44⟩ + (⟨53⟩ x ⟨ 26⟩ ) + (⟨52⟩ x ⟨55⟩ )
⟨52⟩ + ⟨53⟩
For Refrigerant Coils
Note: If ν56ο ≧ ν26ο, coil is fully wet. For this
condition, use ν56ο = ν26ο. If ν56ο < ν26ο,
coil is partially dry.
41
41
51
51
57
Approximate Tube-Side Temperature at Dry-Wet Bounday
F
= ν33ο - ν53ο (ν26ο - ν56ο) - For Water Coils
[ΕC]
= ν44ο - ν53ο (ν26ο - ν56ο) - For Refrigerant Coils
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
ITEM NO.
GENERAL
CATEGORY
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
COLD WATER
COILS
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
42
42
52
52
58
Mean
Tube-Side Temperature for Fully Wet Coil or Wet
Portion of Partially Dry Coil
F
[ΕC]
= 0.5 (ν20ο + ν57ο) - For Partially Dry Water Coil
= 0.5 (ν20ο + ν33ο) - For Fully Wet Water Coil
43
44
43
44
53
54
53
54
RATING PARAMETERS
= 0.5 (ν21ο + ν57ο) - For Partially Dry Volatile
Refrigerant Coils
= 0.5 (ν21ο + ν44ο) - For Fully Wet Volatile
Refrigerant Coils
59
Approximate Mean Air Enthalpy for Fully Wet Coil or Wet
Portion of Partially Dry Coil
Btu per lb
[KJ/Kg]
= 0.5 (ν30ο + ν56ο) - For Partially Dry Coil
= 0.5 (ν26ο + ν30ο) - For Fully Wet Coil
60
Approximate Mean Surface Temperatures for Fully Wet Coil or
Wet Portion of Partially Dry Coil (From Fig . 9 with ν52ο, ν58ο
and ν59ο)
F
[ΕC]
45
45
55
55
61
m"/cp - Air-Side Heat Transfer Multiplier for Wet Surface
(From Fig. 8 with ν60ο and ν23ο)
--
46
46
56
56
62
faW - Air-Side Thermal Conductance for Wet Surface
= ν61ο/ ν50ο
Btu per (hr)
(sq ft) (F)
[W/m2 Α ΕC]
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
CATEG
ITEM
NO.
COLD WATER
COILS
GENER
AL
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
PARTIALLY
WET
SURFACE
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
FULLY
WET
SURFCE
47
47
57
57
63
RmW -
Metal Thermal Resistance for Wet Surface
(From Fig. 2 with ν62ο)
48
48
58
58
64
C
-
Coil Characteristic for Wetted Surface
49
49
59
59
RATING PARAMETERS
=
⟨ 48⟩ + ⟨63⟩
0.243 ⟨50⟩
⎡
⟨ 48⟩ + ⟨ 63⟩ ⎤
⎢C =
⎥
1
.018 ⟨50⟩ ⎦
⎣
(sq ft) (hr)
(F) per Btu
[m2 Α ΕC/W]
(lb) (F)
per Btu
[Kg Α ΕC/KJ]
Note: This is final value for rating convenience.
65
hB
- Air Enthalpy at Boundary
=
Btu per lb
⟨54⟩ − ⟨33⟩ + (⟨53⟩ x ⟨ 26⟩ ) + (⟨64⟩ x ⟨55⟩ )
⟨64⟩ + ⟨53⟩
[KJ/Kg]
For Water Coils
=
⟨54⟩ − ⟨ 44⟩ + (⟨53⟩ x ⟨ 26⟩ ) + (⟨64⟩ x ⟨55⟩ )
⟨64⟩ + ⟨53⟩
For Volatile Refrigerant Coils
If ν65ο < ν26ο, surface is particlaly dry, proceed to ν66ο.
If ν65ο ≧ ν26ο, surface is fully wet, proceed to ν71ο.
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
GENERAL PROCEDURE
Form 410- 9
FULLY
WET
SURFACE
-
60
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
PARTIALLY
WET
SURFACE
50
GENERAL
CATEGORY
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
66
qtD
-
DIMENSIONS
Capacity for Dry Portion of Coil
Btuh
[W]
= ν27ο (ν26ο - ν 65ο)
51
-
61
-
67
tB
-
F
Air Dry-Bulb Temperature at Bounday
= ⟨17⟩ −
⟨ 66⟩
0.243 x ⟨ 27⟩
⎡
⎤
⟨66⟩
⎢ t B = ⟨17⟩ −
⎥
1.018 x ⟨ 27⟩ ⎦
⎣
[ΕC]
52
53
-
-
62
63
-
-
RATING PARAMETERS
Note: This is final value for rating convenience.
68
Tube-Side Temperature at Boundary
F
twB = ν33ο - ν53ο (ν26ο - ν65ο) – For Water Coils
[ΕC]
trB = ν44ο - ν53ο (ν26ο - ν65ο) - For Refrigerant
Coils
69
∆tm - Logarithmic Mean Temperature Difference for Dry
Portion of Coil
=
=
(⟨17⟩ − ⟨33⟩ ) − (⟨ 67⟩ − ⟨68⟩ )
⎡ ⟨17⟩ − ⟨33⟩ ⎤
In ⎢
⎥
⎣ ⟨67⟩ − ⟨68⟩ ⎦
[ΕC]
− For
Water
(⟨17⟩ − ⟨ 44⟩ ) − (⟨ 67⟩ − ⟨68⟩ )
⎡ ⟨17⟩ − ⟨ 44⟩ ⎤
In ⎢
⎥
⎣ ⟨ 67⟩ − ⟨68⟩ ⎦
F
− For
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
FULLY
WET
SURFCE
-
64
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
PARTIALLY
WET
SURFACE
54
GENERAL
CATEGORY
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
70
AcD -
Calculated External Surface Area for Dry
Portion of Coil
55
56
50
51
¤
65
66
60
61
¤
RATING PARAMETERS
=
71
qtW
-
DIMENSIONS
sq ft
[m2]
⟨66⟩ (⟨ 48⟩ + ⟨ 49⟩ + ⟨51⟩ )
⟨ 69⟩
Capacity for Wet Portion of Coil
= ν31ο - ν66ο - For Partially Wet Coils
Btuh
[W]
= ν31ο - For fully Wet Coils
72
tsl
- Surface Temperature at Air Entering Side of Wet
Portion. From Fig. 9 with:
- ν23ο, ν26ο, ν33ο, and ν64ο) - For Totally
Wet Water Coils
F
[ΕC]
- ν23ο, ν26ο, ν44ο, and ν64ο) - For Totally
Wet Volatile Refrigerant Coils
= tsB = ν54ο for Partially Dry Water and Refrigerant Coils
Fig. 9 can be used for determining the surface temperature provided the rating calculations are bsed on a standard barometric pressure of 29.92 in. Hg [101.325 Kpa] ∀0.3 in. Hf
[∀1.014 Kpa]. If the barometric pressure is not within this range, then it is necessary to determine the surface temperature by trial and error, using the following equation: ts = tt + C
(h - hx). Assume a value for ts and correct the corresponding hs at saturation for the barometric pressure.
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
62
¤
¤
¤
¤
59
53
54
68
69
63
64
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
FULLY
WET
SURFCE
67
GENERAL
CATEGORY
PARTIALLY
WET
SURFACE
52
73
RATING PARAMETERS
FULLY
WET
SURFACE
57
58
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
74
ts2
hsl
-
-
Surface Temperature at Air Leaving Side of Wet
Portion. From Fig. 9 with:
-
ν20ο, ν23ο, ν30ο, and ν64ο for Water Coils
-
ν21ο, ν23ο, ν30ο, and ν64ο for Volatile
Refrigerant Coils
Enthalpy of Saturated Air at Air Entering Side of
Wet Portion
DIMENSIONS
F
[ΕC]
Btu per lb
[KJ/Kg]
- From ν23ο and ν72ο - For Fully Wet Coils
= hsB = ν55ο - For Partially Dry Coils
75
hs2
- Enthalpy of Saturated Air at ν23ο and ν73ο
Btu per lb
[KJ/Kg]
Fig. 9 can be used for determining the surface temperature provided the rating calculations are based on a standard barometric pressure of 29.92 in. Hg [101.325 Kpa] ∀0.3 in. Hg
[∀1.014 Kpa]. If the barometric pressure is not within this range, then it is necessary to determine the surface temperature by trial and error, using the following equation: ts = tr + C
(h - hs). Assume a value for tx and correct the corresponding hs at saturation for the barometric pressure.
Form 410- 9
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
FULLY
WET
SURFCE
55
70
65
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
PARTIALLY
WET
SURFACE
60
GENERAL
CATEGORY
FULLY
WET
SURFACE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
76
)hm
-
Logarithmic Mean Enthalpy Difference between
Air Stream and Wetted Surface
61
56
71
66
RATING PARAMETERS
=
=
77
AcW -
(⟨ 26⟩ − ⟨74⟩ ) − (⟨30⟩ − ⟨75⟩ )
⎡ ⟨ 26⟩ − ⟨74⟩ ⎤
In ⎢
⎥
⎣ ⟨30⟩ − ⟨75⟩ ⎦
DIMENSIONS
Btu per lb
[KJ/Kg]
(⟨65⟩ − ⟨74⟩ ) − (⟨30⟩ − ⟨75⟩ )
⎡ ⟨65⟩ − ⟨74⟩ ⎤
In ⎢
⎥
⎣ ⟨30⟩ − ⟨75⟩ ⎦
Calculated External Surface Area for Fully Wet
Coil or Wet Portion of Coil
sq ft
[m2]
= 0.243 x ν50ο x ν71ο/ν76ο
[AcW = 1.018 x ν50ο x ν71ο/ν76ο]
Form 410- 9
62
57
72
67
78
Ac
- Total Calculated External Surface Area
sq ft
= ν77ο + ν70ο for Partially Wet Coil
[m2]
= ν77ο for Fully Wet Coil
Note: For Case I and II in ν28ο, complete ν79ο.
For Case III in ν28ο, complete ν80ο and ν81ο.
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
59
74
69
ITEM NO.
68
GENERAL
CATEGORY
FULLY
WET
SURFCE
73
CACULATION
FOR NO. OF
ROWS FOR
CASES I & II
PARTIALLY
WET
SURFACE
58
79
CALCULATI
ON OF
CAPACITY
FOR CASE
III
FULLY
WET
SURFACE
63
64
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
COLD WATER
COILS
80
Nr
-
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Required Number of Rows of Coil Tubes in
--
Direction of Air Flow =
⟨ 78⟩
⟨3⟩ x ⟨8⟩
If ν78ο ≷ ν12ο, assume a new value of qt ≷ ν31ο. Repeat
calculations from ν26ο through ν78ο. Plot calculated values
of ν78ο against assumed values of ν31ο as shown in Fig. 12c.
--
Form 410- 9
65
60
75
70
81
Determine actual value of qt from plot ν80ο with Ac = ν12ο
Btuh
66
67
61
62
76
77
71
72
CALCULATIONS TO
DETERMINE AIR
LEAVING DRY-BULB
TEMPERATURE
[W]
82
c
=
83
e-c
Heat Transfer Exponent
⟨12⟩ x 60
14.58 x ⟨ 49⟩ x ⟨ 27⟩
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
⎡
⎤
⟨12⟩ x 1000
⎢C =
⎥
1018.2 ⟨ 49⟩ x ⟨ 27⟩ ⎦
⎣
- Heat Transfer Factor = e-ν82ο
COIL LINE _______________________________
--
--
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
GENERAL PROCEDURE
NUMERICAL
VALUES
ITEM NO.
GENERAL
CATEGORY
FULLY
WET
SURFCE
VOLATILE
REFRIGERANT
COILS
PARTIALLY
WET
SURFACE
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
COLD WATER
COILS
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
69
70
71
63
64
65
66
78
79
80
81
73
74
75
76
84
CALCULATIONS TO DETERMINE AIR LEAVING
DRY-BULB TEMPERATURE
68
h2
-
Leaving Air Enthalpy of Actual Value of qt
Btu per lb
⟨31⟩ or ⟨81⟩
⟨ 27⟩
[KJ/Kg]
=
26 −
Note: Knowing ν18ο or ν26ο, ν17ο, ν83ο,
and ν84ο, t2 can be determined from
the following procedure.
85
h
-
Saturated Enthalpy at Effective Surface
Temperature = ⟨ 26⟩ −
86
87
t
t2
-
-
Effective Surface Temperature from Psychrometric Chart with ν23ο and ν85ο
Air Leaving Dry-Bulb Temperature
= ν86ο + (ν17ο - ν86ο) ν83ο
COIL LINE _______________________________
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
⟨ 26⟩ − ⟨30⟩ or ⟨84⟩
1.0 − ⟨83⟩
Btu per lb
[KJ/Kg]
F
[ΕC]
F
[ΕC]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
VOLATILE
REFRIGERANT
COILS
CATEG
ORY
ITEM
NO.
COLD WATER
COILS
GENER
AL
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
DIMENSIONS
Form 410- 9
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
FULLY
WET
SURFCE
67
82
77
73
74
68
69
83
84
78
79
88
AIR-SIDE PRESSURE DROP CALCULATIONS
PARTIALLY
WET
SURFACE
72
89
)psw/Nr
FA
- Air-Side Pressure Drop Per Row at Standard
Conditions (Use wet surface for partially
dry and fully wet coils.)
-
-
From Fig. 5 with ν16ο for Water Coils
-
From Fig. 6 with ν16ο for Volatile Refrigerant
Coils
Dry Surface Air-Side Pressure Drop Correction
Factor =
in water
per row
[Pascal per
row]
--
460 + 0.5 (⟨17⟩ ⟨87⟩ )
17.71 x ⟨ 23⟩
⎡
273.15 + 0.5 (⟨17⟩ + ⟨87⟩ ) ⎤
⎢FA =
⎥
2.909 x ⟨ 23⟩
⎣
⎦
90
(Δp a )JOB
- Air-Side Pressure Drop at Job Conditions
(constant wa)
in. water
[Pa]
75
76
70
71
-
-
SOLUTION PROCEDURE
STEPS FOR SPECIFIC
COIL APPLICATION
-
-
TUBE-SIDE
PRESSURE DROP
CALCULATIONS
= ν88ο x ν89ο x (ν5ο or ν79ο)
91
92
)pt/LeFt
)ph/Ft
- Tube Circuit Water Pressure Drop Parameter
at 60 F [15.6ΕC] Mean Water Temperature
(From Fig. 4 with ν19ο)
- Header, nozzle and tube entrance and exit
losses to be established by manufacturer
at 60F mean water temperature with νΕ19ο
COIL LINE _______________________________
ft water
per ft
[KPa/m]
ft water
[KPa]
COIL TYPE _____________________________
COIL SURFACE _____________________________________________________________________
NUMERICAL
VALUES
Form 410- 9
GENERAL PROCEDURE
-
73
-
-
74
-
-
85
80
ITEM DESCRIPTION
(Encircled items refer to
preceding item numbers)
ITEM NO.
-
GENERAL
CATEGORY
FULLY
WET
SURFCE
72
AIR-SIDE PRESSURE DROP CALCULATIONS
TUBE-SIDE
PRESSURE DROP
CALCULATIONS
-
PARTIALLY
WET
SURFACE
79
VOLATILE
REFRIGERANT
COILS
FULLY
WET
SURFACE
PARTIALLY
WET
SURFACE
COLD WATER
COILS
93
Fh
-
Temperature Correction Factor for Header
Water Pressure Drop (From Fig. 7 with
ν46ο)
94
Ft
-
Temperature Correction Factor for Tube
Circuit Water Pressure Drop (From Fig. 7
with ν46ο)
95
)pw
JOB
- Water Pressure Drop Across Coil at Job
Conditions
= ν92ο x ν93ο + (ν14ο x ν91ο x ν94ο)
96
)pr
- Refrigerant Pressure Drop Through Coil
= ν36ο x ν39ο x ν14ο
DIMENSIONS
--
ft water
[Kpa]
psi
[Kpa]
Signed _________________________________________________________________ Title
______________________________________________________________________
Form 410- 9
CALCULATION OF HEAT TRANSFER COEFFICIENT AND FRICTION FACTOR FOR GLYCOL* COILS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATED AIR-COOLING AND AIR-HEATING COILS
COMPANY
DATE
COIL LINE
COIL TYPE
COIL PHYSICAL DATA
ITEM NO.
GENERAL
CATEGORY
COIL SURFACE
NUMERICAL
VALUES
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
1
Ao – Total External Coil Surface
(From Form 410-1)
sq ft [m2]
2
Di – Tube Inside Diameter (from Form 410-1)
in [mm]
3
Nt – Total Number of Tubes in Coil
4
Lt – Coil Finned Tube Length Exposed to Air Flow
5
B – Surface Ratio (From Form 410-1)
--
6
Nc – Number of Tube Circuits in Coil
--
7
Aix – Total Cross-Section Fluid Flow Area
Inside Tubes = .00545 (ν2ο)2 × ν6ο
[Aix = 7.85 × 10-7 (ν2ο)2 × ν6ο]
--
in [mm]
sq ft [m2]
*The term “Glycol” refers to ethylene glycol solutions only.
Form 410- 9
ITEM NO.
8
9
10
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
Ls = Straight Tube Length per Pass
in [mm]
Kb – Equivalent Length of Coil Circuit Per Return
Le – Total Equivalent Length of Coil Circuit
⎛⎛
⟨ 3⟩ ⎞
⎛ ⟨ 3⟩
⎞⎞
− 1⎟ ⎟⎟
0.0833 ⎜⎜ ⎜ ⟨8⟩
⎟ + ⟨ 9⟩ ⎜
⟨
⟩
⟨
⟩
6
6
⎠
⎝
⎠⎠
⎝⎝
⎡
⎛⎛
⟨3⟩ ⎞
⎛ ⟨3⟩
⎞ ⎞⎤
− 1⎟ ⎟⎟⎥
⎟ + ⟨ 9⟩ ⎜
⎢ L e = 0.001 ⎜⎜ ⎜ ⟨8⟩
⟨ 6⟩ ⎠
⎝ ⟨ 6⟩
⎠ ⎠⎦⎥
⎝⎝
⎣⎢
NUMERICAL
VALUES
in [mm]
ft [m]
TEST RUN NUMBER
1
11
pS– Average Absolute Static Pressure at Coil
12
t1 – Entering Air Dry-Bulb Temperature
°F [°C]
13
t 1′ – Entering Air Wet-Bulb Temperature
°F [°C]
14
h1 - Entering Air Enthalpy
15
t2- Leaving Air Dry-Bulb Temperature
16
Glycol Concentration
17
Va – Standard Air Face Velocity
2
3
4
5
6
In Hg abs
[kPa]
Btu per lb
[kJ/kg]
°F [°C]
Percent by weight
ft per min
[m/s]
Form 410- 9
GENERAL
CATEGORY
ITEM NO.
OBSERVATIONS
AND
CALCULATIONS
tg1 – Entering Glycol Temperature
°F [°C]
19
tg2 – Leaving Glycol Temperature
°F [°C]
20
tgm – Mean Glycol Temperature = 0.5 (ν18ο + ν19ο)
°F [°C]
21
wg – Glycol Flow Rate
22
qs – Average Sensible Cooling Capacity
23
Δtm – Overall Logarithmic Mean Temperature Difference
(⟨12⟩ − ⟨19⟩ ) − (⟨15⟩ − ⟨18⟩ )
=
⟨12⟩ − ⟨19⟩
ln
⟨15⟩ − ⟨18⟩
If other than thermal counterflow, determine the
logarithmic mean temperature difference from
Figures 13, 14, or 15
⟨1⟩ × ⟨ 23⟩
R – Overall Thermal Resistance =
⟨ 22⟩
CALCULATIONS OF GLYCOL THERMAL RESISTANCE
18
24
TEST RUN NUMBER
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
1
2
3
4
5
6
lb per h [g/s]
Btuh [W]
°F [°C]
h sq ft o F
Btu
[m2 ⋅ °C/W]
25
RaD + RmD - Combined Air Film Plus Metal Thermal
Resistance (From Figure 4 with ν17ο)
h sq ft o F
Btu
[m2 ⋅ °C/W]
26
Rg – Film Thermal Resistance of Glycol = ν24ο - ν25ο
h sq ft o F
Btu
[m2 ⋅ °C/W]
27
fg – Glycol Film Heat Transfer Coefficient = ν5ο / ν26ο
Btu
h sq ft o F
ITE
M
GEN
ERA
L
[W/ m2 ⋅ °C]
TEST RUN NUMBER
ITEM DESCRIPTION
DIMENSIONS
Form 410- 9
1
ttw – Average Tube Wall Temperature
= ν20ο + [ν26ο / ν24ο] × ν23ο
3
4
5
6
°F [°C]
29
μtw – Absolute Viscosity of Glycol at ν16ο and ν28ο
lb per ft h
[mPa ⋅ s]
30
μg – Absolute Viscosity of Glycol at ν16ο and ν20ο
lb per ft h
[mPa ⋅ s]
31
dg – Specific Gravity of Glycol at ν16ο and ν20ο
32
cpg – Specific Heat of Glycol at ν16ο and ν20ο
33
kg – Thermal Conductivity of Glycol at ν16ο and ν20ο
-Btu per lb °F
[KJ/kg ⋅ °C]
Btu
h sq ft o F
[W/ m2 ⋅ °C]
34
(μtw / μg) .14 – Viscosity Ratio = (ν29ο /ν30ο).14
--
35
Pr – Prandtl Number = (ν32ο × ν30ο) / ν33ο
--
36
Pr 2/3 = (ν35ο)2/3
--
37
Cg – Mass Velocity of Glycol
38
νg – Kinematic Viscosity of Glycol
= ν30ο / (224,500 × ν31ο)
[νg = ν30ο / ν31ο]
lb per sq ft h
[g/m2 ⋅ s]
sq ft per sec
[mm2 /s]
ITE
M
GEN
ERA
L
CALCULATIONS OF GLYCOL THERMAL RESISTANCE
28
2
TEST RUN NUMBER
ITEM DESCRIPTION
DIMENSIONS
Form 410- 9
39
CALCULATION OF HEAT TRANSFER AND PRESSURE DROP
FACTORS FOR PLOTTING
40
j – Colburn Heat Transfer Factor for Glycol
= [ν27ο / (ν32ο × ν37ο)] (ν23ο × ν34ο)
Vg – Glycol Velocity Inside Tubes =
⟨ 37⟩
224,500 × ⟨ 31⟩
⎡
⎤
⟨ 37⟩
Vg = ⎢
⎥
⎣ 1,000 ,000 ⟨ 31⟩ ⎦
41
Re – Reynolds Number for Glycol =
⟨ 40⟩ × ⟨ 2⟩
12 × ⟨ 38⟩
1000 × ⟨ 40⟩ × ⟨ 2⟩
⟨ 38⟩
Δpg – Glycol Pressure Drop
1
2
3
4
5
6
--
ft per sec
[m/s]
--
Re =
42
43
Δph – Header and Tube Entrance and Exit Loss –
Established by the Manufacturer
44
Δpt /Le – Glycol Pressure Drop Inside Tubes
⟨ 42⟩ − ⟨ 43⟩
=
⟨10⟩
45
f’ – Friction Factor for Glycol
1.34 × ⟨ 2⟩ × ⟨ 44⟩ ⎡
0.00045 × ⟨ 2⟩ × ⟨ 44⟩ ⎤
=
⎥
⎢f ' =
2
⟨ 40⟩ × ⟨ 34⟩ ⎣⎢
⟨ 40⟩ 2 × ⟨ 34⟩
⎦⎥
[
ft of glycol
[kPa]
ft of glycol
[kPa]
ft of glycol per ft
equiv. tube length
[kPa/m]
--
]
46
Plot j vs Re on Logarithmic Coordinates as Shown in Figure
16
-
-
-
-
-
-
47
Plot f’ vs Re on Logarithmic Coordinates as Shown in Figure
16
-
-
-
-
-
-
Form 410- 9
SUGGESTED FORM FOR RATING CALCULATION PROCEDURE FOR
SENSIBLE HEAT AIR COILS WITH ETHLYENE GLYCOL SOLUTIONS
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATED AIR-COOLING AND AIR-HEATING COILS
COMPANY
DATE
COIL LINE
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
COIL TYPE
COIL SURFACE
GENERAL PROCEDURE
1
1
1
H – Coil Face Height
in [mm]
2
2
2
L – Coil Face Length
in [mm]
3
3
3
Af – Coil Face Area
sq ft [m2]
4
4
4
B – Surface Ration (from Form 410-1)
--
-
5
5
Nr – Number of Rows Deep
--
-
6
6
Nt – Total Number of Tubes in Coil
--
5
7
7
Nc – Parallel Tube Circuits in Coil
6
8
8
Ao / Af Nr
-(sq ft) per
(sq ft – F.A.)
(row)
[(sq metre) per
(sq metre – F.A.)
(row)]
-
9
9
Ao = ν8ο × ν3ο × ν5ο
COIL PHYSICAL DATA
ITEM NO.
TO SOLVE FOR
CAPACITY
(qS)
GENERAL
CATEGORY
TO SOLVE
FOR ROWS
DEEP
(NR)
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
NUMERICAL
VALUES
sq ft
[m2]
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM NO.
GENERAL
CATEGORY
GENERAL PROCEDURE
TO SOLVE FOR
CAPACITY
(qs)
7
10
10
Di – Tube Inside Diameter
in [mm]
8
11
11
Aix – Total Cross-Sectional Fluid Flow Area
Inside Tubes = 0.00545 (ν10ο2 × ν7ο)
[Aix = 7.85 × 10 –7 (ν10ο2 × ν7ο)]
sq ft [m2]
9
12
12
Ls – Straight Tube Length per Tube Pass
in [mm]
10
13
13
Kb – Equivalent Length of Coil Circuit per Return
Bend
in [mm]
11
14
14
Ls /Di – Ratio of Tube Length to Diameter
= ν12ο / ν10ο
12
15
15
Qa – Air Volume Flow at Standard Conditions
scfm [l/s]
13
16
16
Va – Standard Air Face Velocity, ν15ο / ν3ο
[Va = 0.001 × ν15ο / ν3ο]
ft per min
[m/s]
14
17
17
t1 – Entering Air Dry-Bulb Temperature
°F [°C]
15
18
18
tg1 - Entering Ethylene Glycol Solution Temperature
°F [°C]
16
19
19
Δto – Initial Air-to-Ethylene Glycol Solution
Temperature =
ν17ο - ν18ο for Air-Cooling Coils
ν18ο - ν17ο for Air-Heating Coils
°F [°C]
RATING CONDITIONS
COIL PHYSICAL DATA
TO SOLVE
FOR ROWS
DEEP
(Nr)
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
NUMERICAL
VALUES
--
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM NO.
GENERAL
CATEGORY
GENERAL PROCEDURE
TO SOLVE FOR
CAPACITY
(qs)
17
20
20
pS – Average Absolute Static Pressure at Coil
18
21
21
wg – Total Ethylene Glycol Solution Flow Rate
19
22
22
wg /Nc – Ethylene Glycol Solution Flow Rate per
Circuit = ν21ο / ν7ο
20
--
23
qs – Coil Sensible Heat (known)
21
--
24
Δta – Air Temperature Rise or Drop Across
⎡
⎤
⟨ 23⟩
⟨ 23⟩
Coil =
⎢ Λt a
⎥
4.5 c p × ⟨15⟩ ⎣⎢
1.2 c p × ⟨15⟩ ⎦⎥
°F [°C]
22
--
25
t2 – Leaving Air Temperature at Coil
= ν17ο - ν24ο for Air-Cooling Coils
= ν17ο + ν24ο for Air-Heating Coils
°F [°C]
23
23
26
Ethylene Glycol Concentration
RATING CONDITIONS
TO SOLVE
FOR ROWS
DEEP
(Nr)
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
NUMERICAL
VALUES
in Hg abs
[kPa abs]
lb per h
[g/s]
lb per (h)
(circuit)
[(gram) per
(second) (circuit)]
Btuh
[W]
percent by weight
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
24
25
25
26
26
27
27
28
28
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM NO.
24
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY
(qs)
ETHYLENE GLYCOL SOLUTION PROPERTIES AND CALCULATIONS
TO SOLVE
FOR ROWS
DEEP
(Nr)
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
27
tgm – Mean Ethylene Glycol Solution Temperature
- when solving for rows deep this value must be
calculated by trial and error using ν26ο and
determining cpg for various values of tgm with
the following equations:
⟨ 23⟩
t gm = ⟨18⟩ +
for Air-Cooling Coils
2 × ⟨ 21⟩ × c pg
t gm = ⟨18⟩ +
-
NUMERICAL
VALUES
°F [°C]
⟨ 23⟩
for Air-Heating Coils
2 × ⟨ 21⟩ × c pg
when solving for capacity, this value must be
approximated (suggest tgm be 5 °F [2.8 °C] to
10 °F [5.6 °C] from ν18ο)
28
cpg – Specific Heat for Ethylene Glycol Solution at
ν26ο and ν27ο
29
dg – Specific Gravity of Ethylene Glycol Solution at
ν26ο and ν27ο
30
kg – Thermal Conductivity of Ethylene Glycol Solution
at ν26ο and ν27ο
31
DIMENSIONS
μg – Absolute Viscosity of Ethylene Glycol Solution at
ν26ο and ν27ο = centipoise × 2.42
Btu /lb ⋅ °F
[KJ/kg ⋅ °C]
--
Btu
h − ft − o F
[W/m ⋅ °C]
lb per ft h
[mPa ⋅ s]
GENERAL PROCEDURE
Form 410- 9
30
30
31
31
32
32
33
33
34
34
35
35
36
36
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM NO.
29
GENERAL
CATEGORY
29
ETHYLENE GLYCOL SOLUTION PROPERTIES AND CALCULATIONS
TO SOLVE FOR
CAPACITY
(qs)
GENERAL
CALUCULATIONS
TO SOLVE
FOR ROWS
DEEP
(Nr)
32
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
νg – Kinematic Viscosity of Ethylene Glycol Solution
= ν31ο / (224,500 × ν29ο) [νg = ν31ο / ν29ο]
DIMENSIONS
NUMERICAL
VALUES
sq ft per sec
[mm2/s]
lb per sq ft h
[g/s ⋅ m2]
33
Gg – Mass Velocity of Glycol = ν21ο / ν11ο
34
Vg – Ethylene Glycol Solution Velocity Inside Tubes =
⎡
⎤
⟨ 33⟩
⟨ 33⟩
Vg =
⎢
224 ,500 × ⟨ 29⟩ ⎣
1,000 ,000 × ⟨ 29⟩ ⎥⎦
35
Re – Reynolds Number for Ethylene Glycol Solution
⟨ 34⟩ × ⟨10⟩ ⎡
1000 × ⟨ 34⟩ × ⟨10⟩ ⎤
=
Re =
⎥
12 × ⟨ 32⟩ ⎢⎣
⟨ 32⟩
⎦
--
36
Pr – Prandtl Number for Ethylene Glycol Solution
⟨ 28⟩ × ⟨ 31⟩
=
⟨30⟩
--
37
Pr2/3 = (ν36ο) 2/3
--
38
j = Colburn Heat Transfer Factor for Ethylene Glycol
Solution at ν35ο and ν14ο and Figure 16
--
39
RaD + RmD – Combined Air Film Plus Metal Thermal
Resistance (From Figure 4 with ν16ο)
h sq ft o F
Btu
[m2 ⋅ °C/W]
ft per sec
[m/s]
GENERAL PROCEDURE
Form 410- 9
37
37
ITEM NO.
TO SOLVE FOR
CAPACITY
(qs)
GENERAL
CATEGORY
TO SOLVE
FOR ROWS
DEEP
(Nr)
40
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
M - Air-to Ethylene Glycol Solution Heat Capacity
4.5 × ⟨15⟩ c p ⎡
1.2 × ⟨15⟩ × c1 ⎤
M=
Ratio =
⎢
⟨ 21⟩ × ⟨ 28⟩ ⎣
⟨ 21⟩ × ⟨ 28⟩ ⎥⎦
--
--
41
E – Air-side Effectiveness = ν24ο / ν19ο
--
39
--
42
co – Heat Transfer Exponent (Air-to-Ethylene Glycol
Solution) – From Figure 13 or 14 or 15 with ν40ο
and ν41ο
--
40
--
43
Δtm – Overall Mean Temperature Difference =
ν24ο / ν42ο
°F [°C]
41
38
44
ttw – Average Tube Wall Temperature
- when solving for rows deep this temperature
must be approximated, suggest
ttw = ν27ο + .5 × ν43ο for Air-Cooling Coils
ttw = ν27ο + .5 × ν43ο for Air-Heating Coils
- when solving for capacity, suggest this
temperature be approximated using ttw about
10 °F[5.6 °C] to 15 °F[8.3 °C] from ν18ο
°F [°C]
42
39
45
μtw - Absolute Viscosity of Ethylene Glycol Solution
at ν26ο and ν44ο
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
GENERAL CALCULATIONS
38
NUMERICAL
VALUES
lb per ft h
[mPa ⋅ s]
GENERAL PROCEDURE
Form 410- 9
ITEM NO.
GENERAL
CATEGORY
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
TO SOLVE
FOR ROWS
DEEP
(Nr)
TO SOLVE FOR
CAPACITY
(qs)
43
40
46
(μtw /μg) .14 – Viscosity Ratio = (ν45ο / ν31ο).14
44
41
47
fg – Ethylene Glycol Solution Film Heat Transfer
⟨ 28⟩ × ⟨ 33⟩ × ⟨ 38⟩
Coefficient =
⟨ 37⟩ × ⟨ 46⟩
DIMENSIONS
NUMERICAL
VALUES
--
42
46
43
47
--
48
--
49
--
50
--
CALCULATIONS TO SOLVE
FOR ROWS DEEP
45
GENERAL CALCULATIONS
Btu
h sq ft o F
[W/ m2 ⋅ °C]
48
Rg – Film Thermal Resistance of Ethylene Glycol
Solution = ν4ο / ν47ο
h sq ft o F
Btu
[m2 ⋅ °C/W]
49
R – Overall Thermal Resistance = ν39ο + ν48ο
h sq ft o F
Btu
[m2 ⋅ °C/W]
50
*ttw – Average Tube Wall Temperature
= ν27ο + (ν48ο / ν49ο) (ν43ο) for Air-Cooling Coils
= ν27ο - (ν48ο / ν49ο) (ν43ο) for Air-Heating Coils
51
Nrc – Calculated Row Depth Required
⟨ 23⟩ × ⟨ 49⟩ × ⟨ 42⟩
=
⟨ 3⟩ × ⟨8⟩ × ⟨ 24⟩
--
52
Nr – Integral Coil Row Depth Installed
--
53
Nt – Total Number of Tubes in Coil
--
°F [°C]
*ν50ο must equal ν44ο within ±3 °F [∀ 1.7 °C]. If not, assume a new value for ν44ο and repeat calculations through ν50ο.
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
GENERAL PROCEDURE
Form 410- 9
ITEM NO.
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY
(qs)
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
--
44
54
co – Heat Transfer Exponent (Air-to-Ethylene Glycol
Solution) =
⎡
⎤
⟨ 9⟩
⟨ 9⟩
⎢c o =
⎥
4.5 c p × ⟨15⟩ × ⟨ 49⟩ ⎢⎣
4.5 c p × ⟨15⟩ × ⟨ 49⟩ ⎥⎦
--
--
45
55
E – Air Side Effectiveness from Figure 13 or 14 or
15 with ν40ο and ν54ο
--
--
46
56
Δta – Air Temperature Rise or Drop Across Coil
= ν55ο × ν19ο
°F [°C]
--
47
57
Δtg – Ethylene Glycol Solution Temperature Rise or
Drop Across Coil = ν56ο × ν40ο
°F [°C]
--
48
58
Δtm – Overall Mean Temperature Difference
= ν56ο / ν54ο
°F [°C]
--
49
59
*tgm – Mean Ethylene Glycol Solution Temperature
*tgm = ν18ο + .5 × ν57ο for Air-Cooling Coils
*tgm = ν18ο - .5 × ν57ο for Air-Heating Coils
°F [°C]
--
50
60
*ttw – Average Tube Wall Temperature
*ttw = ν59ο + [ν48ο / ν49ο] ν58ο for Air-Cooling
Coils
*ttw = ν59ο - [ν48ο / ν49ο] ν58οfor Air-Heating
Coils
°F [°C]
CALCULATIONS TO SOLVE FOR CAPACITY
TO SOLVE
FOR ROWS
DEEP
(Nr)
DIMENSIONS
NUMERICAL
VALUES
*ν59ο must equal ν27ο and ν60ο must equal ν44ο within ± 3 °F [±1.7 °C]. If not, assume new values for ν27ο and ν44ο and repeat calculations through ν60ο.
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
GENERAL PROCEDURE
Form 410- 9
--
51
--
52
51
52
ITEM NO.
TO SOLVE FOR
CAPACITY
(qs)
CALCULATIONS TO GENERAL
SOLVE FOR
CATEGORY
CAPACITY
TO SOLVE
FOR ROWS
DEEP
(Nr)
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
qs – Coil Sensible Heat = 4.5 cp × ν15ο × ν56ο
[qs = 1.2 cp × ν15ο × ν56ο]
62
t2 – Leaving Air Temperature at Coil
= ν17ο - ν56ο for Air-Cooling Coils
= ν17ο + ν56ο for Air-Heating Coils
53
63
Δpst /Nr – Air Side Pressure Drop Per Row Deep at
Standard Conditions (From Figure 3 or 4
with ν16ο)
54
64
Fa – Air-side Pressure Drop Correction Factor
53
55
54
56
55
57
GENERAL CALCULATIONS
61
=
460 + [⟨17⟩ + ⟨ 25⟩ or ⟨ 62⟩ ]
DIMENSIONS
NUMERICAL
VALUES
Btuh
[W]
°F [°C]
in water
row
[Pa / row]
--
17.71 × ⟨ 20⟩
⎡
⎛ ⟨17⟩ + ⟨ 25⟩ or ⟨ 62⟩ ⎞ ⎤
273.15 + ⎜
⎟⎥
⎢
2
⎝
⎠⎥
⎢ Fa =
2
.
909
×
⟨
20
⟩
⎢
⎥
⎢
⎥
⎣
⎦
65
66
67
(Δpa)Job– Air Side Pressure Drop at Job Conditions
(constant wa) = [ν63ο × ν64ο] × ν5ο orν52ο
Le – Total Equivalent Length of Coil Circuit
⎡⎛
⟨ 6⟩ or ⟨ 53⟩
⟨ 6⟩ or ⟨ 53⟩ ⎞ ⎛
⎞⎤
− 1⎟ ⎥
= .0833 ⎢⎜ ⟨12⟩
⎟ + ⎜ ⟨13⟩
⟨
⟩
⟨
⟩
7
7
⎠ ⎝
⎠⎦
⎣⎝
in water
[Pa]
ft [m]
f’ – Friction Factor for Ethylene Glycol Solution from
Figure 16 at ν35ο
--
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
58
57
59
58
60
ITEM NO.
56
GENERAL
CATEGORY
TO SOLVE FOR
CAPACITY
(qs)
GENERAL CALCULATIONS
TO SOLVE
FOR ROWS
DEEP
(Nr)
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
68
Δpt /Le – Ethylene Glycol Solution Pressure Drop
Inside Tubes
⟨ 67⟩ × ⟨ 34⟩ 2 × ⟨ 46⟩ ⎡ ⟨ 67⟩ × ⟨ 34⟩ 2 ⟨ 46⟩ ⎤
=
⎢=
⎥
1.34 × ⟨10⟩
⎣⎢ 0.00045 × ⟨10⟩ ⎦⎥
69
Δph – Header and Tube Entrance and Exit LossEstablished by the Manufacturer
ft of glycol
[kPa]
70
(Δpg ) JOB – Ethylene Glycol Solution Pressure Drop
Across Coil at Job Conditions
= (ν66ο × ν68ο) + ν69ο
ft of glycol
[kPa]
NUMERICAL
VALUES
ft of glycol per ft
equiv. tube length
[kPa]
Form 410- 9
SUGGESTED FORM FOR RATING CALCULATION PROCEDURE FOR COOLING AND DEHUMIDIFYING COILS, WITH ETHYLENE GLYCOL*
SOLUTION, ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY
DATE
COIL LINE
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
COIL TYPE
COIL SURFACE
ITEM NO.
GENERAL
CATEGORY
GENERAL PROCEDURE
WET SURFACE
1
1
1
H – Coil Face Height
in [mm]
2
2
2
L – Coil Face Length
in [mm]
3
3
3
Af – Coil Face Area
sq ft [m2]
4
4
4
B – Surface Ration (from Form 410-1)
--
5
5
5
Nr – Number of Rows Deep (if known)
--
6
6
6
Nt – Total Number of Tubes in Coil (if known)
--
7
7
7
Nc – Parallel Tube Circuits in Coil (if known)
8
8
8
Ao / Af Nr
-(sq ft) per
(sq ft – F.A.)
(row)
[(sq metre) per
(sq metre – F.A.)
(row)]
9
9
9
Di - Tube Inside Diameter
in [mm]
10
10
10
Ls – Straight Tube Length Per Tube Pass
in [mm]
11
11
11
Kb – Equivalent Length of Coil Circuit Per Return
Bend
in [mm]
COIL PHYSICAL DATA
PARTIALLY
WET
SURFACE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
NUMERICAL
VALUES
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
12
13
13
14
14
ITEM NO.
12
GENERAL
CATEGORY
FULLY
WETTTED
SURFACE
COIL PHYSICAL DATA
PARTIALLY
WETTTED
SURFACE
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
12
Ao = ν8ο × ν3ο × ν5ο (if known)
sq ft [m2]
13
Aix – Total Cross-Sectional Fluid Flow Area
Inside Tubes = 0.00545 (ν9ο2 × ν7ο)
[Aix = 7.85 × 10 –7 (ν9ο2 × ν7ο)]
sq ft [m2]
14
Le – Total Equivalent Length of Coil Circuit
⎛⎛
⟨ 6⟩ ⎞
⎛ ⟨ 6⟩
⎞⎞
− 1⎟ ⎟⎟
0.0833 ⎜⎜ ⎜ ⟨10⟩
⎟ + ⟨11⟩ ⎜
⟨ 7⟩ ⎠
⎝ ⟨ 7⟩
⎠⎠
⎝⎝
ft [m]
⎡
⎛⎛
⟨6⟩ ⎞
⎞ ⎞⎤
⎛ ⟨6⟩
− 1⎟ ⎟⎟⎥
⎟ + ⟨11⟩ ⎜
⎢ L e = 0.001 ⎜⎜ ⎜ ⟨10⟩
⟨ 7⟩ ⎠
⎝ ⟨7⟩
⎠ ⎠⎦⎥
⎝⎝
⎣⎢
Ls/Di– Ratio of Tube Length to Diameter
= ν10ο / ν9ο
15
15
16
16
16
Qa – Air Volume Flow at Standard Conditions
scfm [l /s]
17
17
17
ft per min
[m/s]
18
Va – Standard Air Face Velocity = ν16ο / ν3ο
[Va = 0.001 × ν16ο / ν3ο]
t1 – Entering Air Dry-Bulb Temperature
19
t 1′ - Entering Air Wet-Bulb Temperature
°F [°C]
20
wg- Total Ethylene Glycol Solution Flow Rate
lb per h
[g/s]
21
tg1 – Entering Ethylene Glycol Solution Temperature
°F [°C]
22
Ps – Average Absolute S. P. at Coil
19
19
20
20
21
21
22
22
RATING CONDITIONS AND DATA
COMPUTATIONS
15
NUMERICAL
VALUES
--
°F [°C]
in Hg abs
[kPa abs]
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
24
24
25
26
25
26
ITEM NO.
23
GENERAL
CATEGORY
23
RATING CONDITIONS
& DATA
COMPUTATION
FULLY
WETTED
SURFACE
RATING CONDITIONS, PARAMETERS &
DATA COMPUTATIONS
PARTIALLY
WETTED
SURFACE
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
23
h1= Entering Air Enthalpy (from ν18ο, ν19ο & ν22ο)
24
Wg / Nc – Ethylene Glycol Solution Flow Rate per
circuit = ν20ο / ν7ο,
25
t 1′′ – Entering Air Dew Point Temperature (from
psychrometric chart with ν18ο, ν19ο & ν22ο
Calculation of Dew Point temperature for non std. air
pressure*:
⎛ (⟨ 22⟩ − p ′) (⟨18⟩ − ⟨19⟩ ) ⎞
⎟⎟
Pv = p ′ − ⎜⎜
2830 − 1.44 (⟨19⟩ )
⎝
⎠
⎡
⎛ (⟨ 22⟩ − p ′) (⟨18⟩ − ⟨19⟩ ) ⎞⎤
⎟⎟⎥
⎢ Pv = p ′ − ⎜⎜
⎢⎣
⎝ 1548.4 − 1.33 (⟨19⟩ ) ⎠⎥⎦
where: p’ = Saturation Vapor Pressure at ν19ο,
from Steam Tables….
Pv = Saturation Vapor Pressure at Dew Point
Temperature….
t 1′′ = Dew Point Temperature is Saturated
Temperature corresponding to Pv , from
Steam Tables…
26
h1′′ = Saturated Enthalpy at Dew Point
(from Psychrometric Chart with ν22ο / ν25ο)
DIMENSIONS
NUMERICAL
VALUES
Btu per lb [kJ/kg]
sq ft [m2]
°F [°C]
In Hg abs
[kPa abs]
°F [°C]
Btu per lb [kJ /kg]
* Jordan and Prelester, Refrigeration and Air Conditioning, 2nd Edition, 1956
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM NO.
GENERAL
CATEGORY
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
27
RaD – Air Film Thermal Resistance for Dry Surface
(from Figure 5 or 6 with ν17ο)
RaW – Air Film Thermal Resistance for Wetted Surface
(from Figure 5 or 6 with ν17ο)
(h) (sq ft) (F) per
Btu [m2 ⋅ °C/W]
(h) (sq ft) (F) per
Btu [m2 ⋅ °C/W]
RmD – Metal Thermal Resistance for Dry Surface
(from Figure 2 at fa = 1/ν27ο)
Ethylene Glycol Concentration
(h) (sq ft) (F) per
Btu [m2 ⋅ °C/W]
Percent by weight
FULLY
WETTED
SURFACE
27
27
28
28
28
29
29
30
30
31
31
32
32
33
33
34
34
RATING CONDITIONS, PARAMETERS AND DATA
COMPUTATIONS
PARTIALLY
WETTED
SURFACE
29
30
31
32
60 wa – Standard Air Flow Rate = 4.5 × ν16ο
[1000 wa = 1.2 × ν16ο]
Case I - If ν33ο is known, determine ν34ο at ν33ο
saturated, and ν22ο. Then calculate
ν35ο = ν31ο (ν23ο - ν34ο).
Case II - If ν35ο is known, determine ν34ο and then
ν33ο. ν34ο = ν23ο - ν35ο / ν31ο.
Case III - If ν5ο is known, assume ν35ο or ν33ο find
ν34ο and then ν33ο or ν35ο respectively.
33
t ′2 – Leaving Air Wet-Bulb Temperature
34
h 2 - Leaving Air Enthalpy – It qt is known,
h 2 = ⟨ 23⟩ −
NUMERICAL
VALUES
lb per h [g/s]
--
°F [°C]
Btu per lb [kJ / kg]
qt
⟨ 31⟩
Form 410- 9
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
35
36
36
37
37
38
38
39
39
40
40
ITEM NO.
35
GENERAL
CATEGORY
FULLY
WETTED
SURFACE
RATING CONDITIONS, PARAMETERS AND DATA
COMPUTATIONS
PARTIALLY
WETTED
SURFACE
GENERAL PROCEDURE
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
DIMENSIONS
35
qt – Total Heat Capacity of Coil = ν31ο (ν23ο - ν34ο)
If not known, assume value for trial and error
solution
tgm – Mean Ethylene Glycol Solution Temperature –
when capacity is know, this value must be calculated
by trial and error using ν30ο and determining cpg for
various values of tgm using the following equation:
⟨ 35⟩
t gm = ⟨ 21⟩ +
2 × ⟨ 20⟩ × c pg
Btu [W]
36
37
38
39
40
cpg – Specific Heat of Ethylene Glycol Solution at
ν30ο and ν36ο
dg – Specific Gravity of Ethylene Glycol Solution at
ν30ο and ν36ο
kg – Thermal Conductivity of Ethylene Glycol
Solution at ν30ο and ν36ο
μg – Absolute Viscosity of Ethylene Glycol
Solution at ν30ο and ν36ο
NUMERICAL
VALUES
°F [°C]
Btu per (lb °F)
[kJ / kg °C]
--
Btu
[W / m ⋅ °C]
h ⋅ ft ⋅ °F
lb per (ft h)
[mPa ⋅ s]
[Note: μg (lb / ft ⋅ h) = 2.42 × μg (centipoise)]
Form 410- 9
GENERAL PROCEDURE
41
41
42
42
43
43
44
44
45
45
46
46
47
47
48
48
ITEM NO.
FULLY
WETTED
SURFACE
41
RATING CONDITIONS, PARAMETERS AND DATA
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
νg – Kinematic Viscosity of Ethylene Glycol Solution
= ν40ο / (224,500 × ν38ο)
⟨ 40⟩ ⎤
⎡
⎢ ν g = ⟨ 38⟩ ⎥
⎣
⎦
42
Gg – Mass Velocity of Glycol = ν20ο / ν13ο
43
Vg – Ethylene Glycol Solution Velocity Inside
⎡
⎤
⟨ 42⟩
⟨ 42⟩
Vg =
Tubes =
⎢
224 ,500 × ⟨ 38⟩ ⎣
1,000,000 × ⟨ 38⟩ ⎥⎦
DIMENSIONS
sq ft per sec
[mm2 /s]
lb per (sq ft – h)
[g m2 ⋅ s]
ft per sec
[m/s]
44
Re – Reynolds Number for Ethylene Glycol Solution
⟨ 43⟩ × ⟨ 9⟩ ⎡
1000 x ⟨ 43⟩ × ⟨ 9⟩ ⎤
=
Re =
⎢
⎥
12 × ⟨ 41⟩ ⎣
⟨ 41⟩
⎦
--
45
Pr – Prandtl Number for Ethylene Glycol Solution
⟨ 37⟩ × ⟨ 40⟩
=
⟨ 39⟩
2/3
Pr = (ν45ο) 2/3
--
47
j – Colburn Heat Transfer Factor for Ethylene Glycol
Solution at ν44ο and ν15ο from Figure 16
--
48
tg2 – Leaving Ethylene Glycol Solution Temperature
= ν21ο + ν35ο / (ν20ο × ν37ο)
°F [°C]
46
NUMERICAL
VALUES
--
Form 410- 9
GENERAL PROCEDURE
49
49
50
50
51
51
52
52
53
53
54
54
55
55
ITEM NO.
FULLY
WETTED
SURFACE
49
RATING CONDITIONS, PARAMETERS AND DATA
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
50
51
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
Y –Ratio of Tube-Side Temperature Difference to Air
Enthalpy Difference
= (ν21ο - ν48ο / (ν23ο - ν34ο)
ttw – Average Tube Wall Temperature (Approximate
when solving for rows deep or capacity) assume 10 to
15 °F [5.6 to 8.3 °C] from ν36ο
μtw – Absolute Viscosity of Ethylene Glycol Solution
at ν30ο and ν50ο
DIMENSIONS
NUMERICAL
VALUES
(lb) (°F)
per Btu
[kg ⋅ °C/kJ]
°F [°C]
lb per ft h
[mPa ⋅s]
52
(μtw / μg).14 – Viscosity Ratio = (ν51ο / ν40ο).14
53
fg – Ethylene Glycol Solution Film Heat Transfer
⟨ 37⟩ × ⟨ 42⟩ × ⟨ 47⟩
Coefficient =
⟨ 46⟩ × ⟨52⟩
Btu per (h) (sq ft)
(°F)
[W/m2 ⋅ °C]
54
Rg – Film Thermal Resistance of Ethylene Glycol
Solution = ν4ο / ν53ο
55
Approximate Coil Characteristic =
⟨54⟩ + ⟨ 29⟩ ⎡ ⟨54⟩ + ⟨ 29⟩ ⎤
0.243 × ⟨ 28⟩ ⎢⎣ 1.018 × ⟨ 28⟩ ⎥⎦
(h) (sq ft) (°F) per
Btu
[m2 ⋅ °C/W]
(lb) (°F) per Btu
[kg ⋅ °C/kJ]
--
used to obtain Rmw in ν63ο
Form 410- 9
GENERAL PROCEDURE
56
56
57
57
58
58
59
59
60
60
61
61
62
62
ITEM NO.
FULLY
WETTED
SURFACE
56
RATING CONDITIONS, PARAMETERS AND DATA
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
57
58
59
60
61
62
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
Approximate Air Enthalpy at Boundary Conditions
⟨ 25⟩ − ⟨ 48⟩ + (⟨ 49⟩ × ⟨ 23⟩ ) + (⟨55⟩ × ⟨ 26⟩ )
=
⟨ 49⟩ + ⟨55⟩
If ν56ο > ν23ο use ν56ο = ν23ο since coil is fully wet
Approximate Tube Side Temperature at Dry-Wet
Boundary = ν48ο - ν49ο (ν23ο - ν56ο)
Mean Tube Side Temperature
= 0.5 (ν21ο + ν57ο) for partially dry coil
= 0.5 (ν21ο + ν48ο) for fully wet coil
Approximate Mean Air Enthalpy of Wetted Section
= 0.5 (ν56ο + ν34ο) for partially dry coil
= 0.5 (ν23ο + ν34ο) for fully wet coil
Approximate Mean Surface Temperature for Fully
Wetted Coil or Wet Portion of Partially Dry Coil
(from Figure 9 with ν55ο, ν58ο, and ν59ο)
m” /cp – Air-Side Heat Transfer Multiplier for Wet
Surface (from Figure 8, with ν60ο and ν22ο)
faw – Air-Side Thermal Conductance for Wet Surface
= ν61ο / ν28ο
DIMENSIONS
NUMERICAL
VALUES
Btu per lb
[kJ /kg]
°F [°C]
°F [°C]
Btu per lb
[kJ/kg]
°F [°C]
-(Btu per (h) (sq ft)
(°F)
[W/m2 ⋅ °C]
Form 410- 9
GENERAL PROCEDURE
63
63
64
64
65
65
66
67
66
--
ITEM NO.
FULLY
WETTED
SURFACE
RATING CONDITIONS, PARAMETERS AND DATA
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
63
Rmw – Metal Thermal Resistance for Wet Surface
(from Figure 2 with ν62ο})
64
C – Coil Characteristic for Wetted Surface
⟨54⟩ + ⟨ 63⟩ ⎡
⟨54⟩ + ⟨ 63⟩ ⎤
C=
=
⎢
0.243 × ⟨ 28⟩ ⎣
1.018 × ⟨ 28⟩ ⎥⎦
65
hB – Air Enthalpy at Boundary
⟨ 25⟩ − ⟨ 48⟩ + (⟨ 49⟩ × ⟨ 23⟩ ) + (⟨ 64⟩ ⟨ 26⟩ )
=
⟨ 49⟩ + ⟨ 64⟩
66
67
If ν65ο < ν23ο, surface is partially dry
If ν65ο ≥ ν23ο, surface is fully wet
hm – Mean Air Enthalpy = 0.5 (ν23ο + ν34ο)
For partially Dry Coil: If ν66ο ≥ ν65ο
Complete items ν67ο and ν68ο
If ν66ο < ν65ο, complete items ν69ο, ν70ο
and ν71ο
For Fully Wet Coils complete items ν69ο, ν70ο
and ν71ο
(See Figures on Last Page of This Form)
tm – Air Dry Bulb Temperature Where Tube Side
Temperature Equals tgm
= ν48ο - (0.5 × ν35ο) / (0.243 × ν31ο)
= ν48ο - (0.5 × ν35ο) / (1.018 × ν31ο)
DIMENSIONS
NUMERICAL
VALUES
(sq ft) (h) (°F) per
Btu
[m2 ⋅ °C/W]
(lb) (°F)
per Btu
[kg ⋅ °C/kJ]
Btu per lb
[kJ/kg]
Btu per lb
[kJ/kg]
°F [°C]
Form 410- 9
GENERAL PROCEDURE
68
--
69
67
70
68
71
69
72
--
73
--
74
--
ITEM NO.
FULLY
WETTED
SURFACE
RATING CONDITIONS, PARAMETERS AND DATA
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
68
69
70
71
72
73
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
* ttw – Average Tube Wall Temperature
= ν36ο + ν54ο (ν67ο - ν36ο / (ν27ο + ν29ο
+ ν54ο)
tsm – Surface Temperature Where Tube Side
Temperature Equals tgm
From Figure 9 with ν22ο, ν36ο, ν64ο, and ν66ο
hsm – Enthalpy of Saturated Air at ν69ο and ν22ο
*ttw – Average Tube Wall Temperature
= ν36ο + ν54ο (ν66ο - ν70ο) / (0.243 × ν28ο)
= ν36ο + ν54ο (ν66ο - ν70ο) / (1.018 × ν28ο)
qtD – Capacity for Dry Portion of Coil
= ν31ο (ν23ο - ν65ο)
tB – Air Dry-Bulb Temperature at Boundary
⎡
⎤
⟨ 72⟩
⟨ 72⟩
t B = ⟨18⟩
= ⟨18⟩ −
⎢
0.243 × ⟨ 31⟩ ⎣
1.018 × ⟨ 31⟩ ⎥⎦
DIMENSIONS
NUMERICAL
VALUES
°F [°C]
°F [°C]
Btu per lb
[kJ/kg]
°F [°C]
Btuh
[W]
°F [°C]
74
tgB – Tube Side Temperature at Boundary
Temperature Equals tgm
°F [°C]
= ν48ο - ν49ο (ν23ο - ν65ο)
* ν68ο or ν71ο must equal ν50ο within ± 3 °F [± 1.7 °C]. If not assume a new value for ν50ο and repeat
calculations through ν68ο or ν71ο.
Form 410- 9
GENERAL PROCEDURE
FULLY
WETTED
SURFACE
75
--
76
--
ITEM NO.
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
75
Δtm – Logarithmic Mean Temperature Difference for
Dry Portion of Coil
(⟨18⟩ − ⟨ 48⟩ ) − (⟨73⟩ − ⟨ 74⟩ )
=
⎛ ⟨18⟩ − ⟨ 48⟩ ⎞
⎟⎟
ln ⎜⎜
⎝ ⟨ 73⟩ − ⟨ 74⟩ ⎠
76
77
70
77
78
71
78
79
72
79
80
73
80
AcD – Calculated External Surface Area for Dry
Portion of Coil
⟨ 72⟩ (⟨ 27⟩ + ⟨ 29⟩ + ⟨54⟩ )
=
⟨ 75⟩
qtW – Capacity for Wet Portion of Coil
= ν35ο - ν72ο for partially wet coils
= ν35ο for fully wet coils
ts1 – Surface Temperature at Air Entering Side of Wet
Portion = tsB = ν25ο for partially dry coils
From Figure 9 with ν22ο, ν23ο, ν48ο and ν64ο
for fully wet coil
ts2 – Surface Temperature at Air Leaving Side of Wet
Portion from Figure 9 with ν21ο, ν22ο, ν34ο,
and ν64ο
hs1 – Enthalpy of Saturated Air at ν78ο and ν22ο
DIMENSIONS
NUMERICAL
VALUES
°F [°C]
sq ft [m2]
Btuh
[W]
°F [°C]
°F [°C]
Btu per lb
[kJ/kg]
Form 410- 9
GENERAL PROCEDURE
74
82
75
83
84
85
76
77
78
ITEM NO.
81
RATINGS PARAMETERS AND DATA
COMPUTATIONS
FULLY
WETTED
SURFACE
CALC. ROWS – FOR
ROWS I AND II
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
81
hs2 – Enthalpy of Saturated Air at ν79ο andν22ο
82
Δhm – Logarithmic Mean Enthalpy Difference
between Air Stream and Wetted Surface
(⟨ 23⟩ − ⟨80⟩ ) − (⟨34⟩ − ⟨81⟩ ) For Fully Wet Coil
=
⎛ ⟨ 23⟩ − ⟨80⟩ ⎞
⎟⎟
In ⎜⎜
⎝ ⟨ 34⟩ − ⟨81⟩ ⎠
83
84
85
NUMERICAL
VALUES
Btu per lb
[kJ/kg]
Btu per lb
[kJ/kg]
(⟨65⟩ − ⟨80⟩ ) − (⟨34⟩ − ⟨81⟩ )
For Partially Dry Coil
⎛ ⟨ 65⟩ − ⟨80⟩ ⎞
⎟⎟
In ⎜⎜
⎝ ⟨ 34⟩ − ⟨81⟩ ⎠
AcW – Calculated External Surface Area for Fully Wet
Coil or Wet Portion of Coil
= 0.243 × ν28ο × ν77ο / ν82ο
[Acw = 1.018 × ν28ο × ν77ο / ν82ο]
Ac – Total Calculated External Surface Area
= ν83ο + ν76ο for partially wet coils
= ν83ο for fully wet coil
Note: For Case I and II in ν32ο, complete ν86ο
For Case III in ν32ο, complete ν86ο and ν87ο
Nr – Required Number of Coil Tubes in Direction of
⟨84⟩
Air Flow
=
⟨ 3⟩ × ⟨8⟩
=
DIMENSIONS
sq ft
[m2]
sq ft
[m2]
--
Form 410- 9
GENERAL PROCEDURE
79
87
80
88
81
89
82
90
83
91
92
84
85
ITEM NO.
86
CALC. ROWS FOR CASE
III
FULLY
WETTED
SURFACE
CALCULATIONS TO DETERMINE
AIR LEAVING DRY-BULB
TEMPERATURE
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
86
87
88
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
If ν84ο ≠ ν12ο, assume a new value of qt ≠ ν35ο
Repeat calculations from ν32ο through ν84ο. Plot
calculated values of ν84ο. Against assumed values of
ν35ο as Shown in Figure 12c.
Determine actual value of qt from plot ν86ο with
Ao = ν12ο.
c- Heat Transfer Exponent
⎡
⎤
⟨12⟩ × 60
⟨12⟩
c=
=
⎢
14.58 × ⟨ 27⟩ × ⟨ 31⟩ ⎣
1.018 × ⟨ 27⟩ × ⟨ 31⟩ ⎥⎦
89
e-c – Heat Transfer Factor = eν-88ο
90
h2 – Saturated Enthalpy at Effective Surface
Temperature
⟨ 23⟩ − ⟨ 34⟩ or ⟨ 90⟩
= ⟨ 23⟩ −
1.0 − ⟨89⟩
DIMENSIONS
NUMERICAL
VALUES
--
Btuh
[W]
--
--
91
h s - Saturated Enthalpy at Effective Surface
⟨ 23⟩ − ⟨ 34⟩ or ⟨ 90⟩
Temperature = ⟨ 23⟩ −
1.0 − ⟨89⟩
92
t s - Effective Surface Temperature From
Psychrometric Chart with ν22ο and ν91ο.
Btu per lb
[kJ/kg]
Btu per lb
[kJ/kg]
°F [°C]
Form 410- 9
GENERAL PROCEDURE
93
86
95
96
97
98
87
88
93
89
90
91
94
95
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
t2 – Air leaving Dry Bulb Temperature
= ν92ο + (ν18ο - ν92ο) ν89ο
Δ psw /Nr - Air Side Pressure Drop per Row Deep at
Standard Conditions (Use Wet Surface for Partially
Dry and Fully Wet Coils.)
- From Figure 5 with ν17ο
Fa - Air Side Pressure Drop Correction Factor
=
96
TUBE SIDE PRESSURE
DROP CALCULATIONS
94
ITEM NO.
FULLY
WETTED
SURFACE
AIR SIDE PRESSURE DROP
CALCALCULATIONS
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
97
98
460 + 0.5 (⟨18⟩ + ⟨ 93⟩ )
17.71 × ⟨ 22⟩
⎡ 273.15 + 0.5(⟨18⟩ + ⟨ 93⟩ ) ⎤
Fa = ⎢
⎥
2.909 × ⟨ 22⟩
⎣
⎦
(Δpa)JOB – Air Side Pressure Drop at Job Conditions
(Constant wa)
ν94ο × ν95ο × (ν5ο or ν85ο)
f’ – Friction Factor for Ethylene Glycol Solution from
Figure 16 at ν44ο
ΔPt /Le – Ethylene Glycol Solution Pressure Drop
Inside tubes
⟨ 97⟩ − ⟨ 43⟩ 2 × ⟨52⟩ ⎡
⟨97⟩ × ⟨ 43⟩ 2 × ⟨52⟩ ⎤
Δ
=
/
P
Le
=
⎢ t
⎥
1.34 − ⟨ 9⟩
0.00045 × ⟨9⟩ ⎦
⎣
DIMENSIONS
NUMERICAL
VALUES
°F [°C]
in water
per row
[Pascal per row]
--
in water
[Pa]
--
ft of glycol per ft
equiv. tube length
[kPa/m]
Form 410- 9
GENERAL PROCEDURE
99
92
100
Signed
93
ITEM NO.
FULLY
WETTED
SURFACE
TUBE SIDE
PRESSURE
DROP
CALCUL.
PARTIALLY
WETTED
SURFACE
GENERAL
CATEGORY
SOLUTION PROCEDURE STEPS
FOR SPECIFIC COIL
APPLICATION
99
100
ITEM DESCRIPTION
(Encircled items refer to preceding item numbers)
Δph - Header and Tube Entrance and Exit Loss –
Established by the Manufacturer
(Δpg) JOB – Ethylene Glycol Solution Pressure Across
Coil at Job Conditions
= (ν14ο × ν98ο) + ν99ο
DIMENSIONS
NUMERICAL
VALUES
ft of glycol
[kPa]
ft of glycol
[kPa]
Title
Form 410- 9
TYPICAL THERMAL COUNTERFLOW DIAGRAMS FOR
PARTIALLY DRY ETHYLENE GLYCOL SOLUTION COILS
For ν66ο < ν65ο
TEMPERATURE OR ENTHALPY
t1, h1
Dry Portion
Wet Portion
tB, hB
hm
ts1
ts2, hs2
t”1
tsm, hsm
tsB, hsB
ts2, hs2
ttw
tg2
tgB
tgm
tg1
SURFACE
For ν66ο > ν65ο
TEMPERATURE OR ENTHALPY
t1, h1
Dry Portion
Wet Portion
hm
ts1
tB, hB
t2, h2
tsm, hsm
t”1
ttw
tsB, hsB
ts2, hs2
tg2
tgm
tgB
Form 410- 9
tg1
SURFACE
Form 410- 9
PRODUCTION COIL LINE CERTIFICATION
ARI CERTIFICATION PROGRAM FOR FORCED-CIRCULATION AIR-COOLING AND AIR-HEATING COILS
COMPANY
DATE
This will certify that the coils lines listed below have been rated on the basis of tests on production coils, or prototypes which are identical to the coils
which will be produced.
COIL LINE
DESIGNATION
PRODUCTION
(P)
OR
PROTOTYPE
(PX)
TUBE
FLUID
USED
O.D.
in
SPACING
sf /sr
ARRANGEMENT
– Parallel or
Staggered
FIN
CONFIGURATION
CONSTRUCTION
Form 410- 9
Signed
Title
Form 410- 9