KUKEN COOLING TOWER
(Series 07)
TYPE: SKB & KMB
(OPEN & CLOSED TYPE COOLING TOWER)
OPERATING MANUAL
CONTENTS
Prior to operation
Important Notice
Warranty
Precaution in safety
Warning Sticker and Nameplate
Other stickers
General Notice
Cooling Tower Parts
Open type Cooling Tower
Closed type Cooling Tower
Fan unit
P2
P3
P4
P5
P6
P7
P8
P8
P10
P12
Precaution in cooling tower operation
Precaution in operation
Precaution in trial operation
Precaution in starting operation
Precaution during winter care
Precaution in halting
Precaution in long term out of operation
Thank you very much for purchasing KUKEN
cooling tower.

Prior to use of the product, please read this
manual carefully and fully understand the
content.

Keep this manual handy whenever necessary
for your daily inspection.
P13
P13
P18
P24
P26
P26
Cleaning and Inspection
Cleaning and inspection
Daily Inspection
Regular Inspection
Parts replacement
Adjustment procedure
Cleaning work
Retaining cooling tower performance
Calculation of make up water
Water quality control
Consumable Parts List
P27
P28
P29
P32
P34
P37
P42
P42
P43
P45
For enquiry
For enquiry
Troubleshooting
P47
P47
Kuken Kogyo Co., Ltd.
Issuing date : 2009. 09 First edition
Important Notice
 Purpose of use

Kuken cooling tower is used to cool water coming in from chiller or other equipments. Do
not use it for the purpose/application other than those stipulated in this manual.
 To those whom concerned

This Operation Manual is directed to those who get involved in operation, maintenance,
and inspection work of this product.
 About this Operation Manual

This Manual is copyrighted. Duplication of this material(whole or partial) is not permitted
without the consent of Kuken. It is also not permitted to copy the content to rewritable
electric device.

The product or parts (sketched, illustrated, or pictured) shown in this manual may give a
different view to the actual goods. And some of illustration could somewhat be simplified to
facilitate our task of elucidating cooling tower internal.

Cooling tower equipped with optional parts may look different from that illustrated in this
manual. (Contact us for further detail on optional parts)

The manual could be revised without any prior notice.

If this manual becomes illegible, contact Kuken for a new copy.

Should you have any enquiry, please contact Kuken head office (indicated on back page.)
 Safety precaution

We might not be able to foresee every possible occasion of accident in the application of
Kuken cooling tower. In this way, this manual may fall short of covering unexpectable
danger.

If modification is required, contact Kuken. Improper modification could cause deterioration
of cooling tower performance as well as insecurity of your safety.
2
Warranty

We will repair/replace at our own cost for malfunction/damage caused within the period
covered by this warranty provided that the product could have been used as properly as so
indicated in this Operation Manual.

Consult us for Regular Inspection. Cooling tower is not covered with warranty if the
inspection has not been done properly following the manual.

The warranty is only valid for the original buyer who purchased the product initially. It is
not applicable for the secondhand buyers.
 Warranty term

Within 1 year from the commissioning date.
 Escape clause
Any malfunction/damage caused on cooling tower fit into the cases described below is not
subject to our product guarantee as still covered it may be for the time remaining；













Any malfunction or damage in consequence of applying cooling tower for the purpose other
than that stipulated herein.
Physical shock accidentally given during relocation/transportation
In consequence of improper mending or modification
Caused by abnormal voltage
Consumable parts for replacement (such as bearing, V-belt, Strainer)
Claim filed without this warranty certificate
No information verifying the purchase is available on warranty certificate (Date of
purchase, name of distributor in the warranty certificate) or those have been rewritten,
Caused by operation and maintenance deliberately done exceeding the capacity limit of the
product.
Caused by application of replacement parts other than those recommended by Kuken.
By natural disaster such as earthquake, typhoon, flood, lightening or fire.
Due to environmental factors (location and its ambient character) enhancing
aging/corrosion.
After having been resold or relocated.
Deterioration by aging
3
Precaution in safety
Prior to operation, read this section for your safety. Instruction herein contains extremely
important notice in regard with safety. Make sure to follow the instruction with the indicated
sign.

The sign below indicates wounding or extent of physical damage resulting from misuse.
Sign indicating accident resulting injury or death or damage on physical property.
WARNING
indicates there is a possibility of serious wounding and death in consequence
of improper usage (handling).
CAUTION
indicates there is a possibility of serious damage of equipments and physical
properties in consequence of improper usage (handling).
indicates matter for you to keep in mind.
Note

The sign indication below shows the “MUST” (some examples are shown below)
(e.g)
DON’T BREAK
APART
DON’T
TOUCH
Indicating DON’T EVER DO
Illustration indicating DON’T EVER DO are shown inside or
nearby
mark.
(e.g)
PLUG OUT
REQUIRES
EARTHING
Indicating MUST DO
Illustration indicating MUST DO are shown inside or
nearby
mark.
(e.g)
ELECTRIC
SHOCK
Indicating CAUTION
Illustration indicating CAUTION are shown inside or
JAM HANDS
nearby
mark.
4
 Warning Sticker and Nameplate
5
EN
 Other stickers
<FAN>
(*1)
For Large cooling tower : on the side of Lower basin tank
For Small cooling tower : on Outside Panel
6
 General Notice
Warning
DO NOT
ENTER
DON’T
BREAK
APART
POWER
OFF
LICENCE
HOLDER
REQUIRES
EARTHIN
G
DURING
WORK
Other than the purpose of inspection,
do not enter (or climb up on) tower.
If you ignore the warning, you could get
injured.
Products should not be broken apart or
dismantled unless done by an expert
possessing license.
If you ignore the warning, it could cause
a burn, electric shock and wounding.
Make sure to check that Fan, Spray
pump, Electric heater and others have
been switched off.
If you ignore the warning, it could cause
a burn or electric shock.
Electric wiring should be done by an
expert possessing license.
If you ignore the warning, it could cause
electric shock and short circuit.
Make sure to carry out earth-wiring first
before doing wiring.
If you ignore the warning, it could cause
electric shock.
During maintenance and inspection
work, exercise care not to swallow cooling
water and not to inhale droplet.
Make sure to gargle and wash hand after
inspection work.
If you ignore the warning, it could affect
your health.
DO NOT
ENTER
Do not enter (climb up on) tower while fan is
in operation.
If you ignore the warning, you could get
injured or you could even be in danger of
death.
MAINTEN
ANCE &
INSPECTI
ON
More than 2 persons are required on duty for
safety reason.
Some parts may accidentally fall down if it is
too heavy for one person to hold. Injury or
damage on product can be expected.
POWER
CUT
DO NOT touch electric heater even after
power was switched off.
If you ignore the warning, it could cause a
burn.
PROTECT
ION
Secure foot space and wear protective on the
top of cooling tower.
If you ignore the warning, you could get
injured.
Make sure that capacity of power supply,
control panel, and switching device be
appropriate.
If you ignore the warning, it could cause fire,
electric shock due to the excessive current
and short circuit, leading death or wounding.
CHECK
Do proper wiring to avoid leaking and short
circuit of electricity.
If you ignore the warning, it could cause
electric shock.
LEAKING
/ SHORT
CIRCUIT
Caution
DO NOT
STICK IN
Do not stick hand or foreign substance
into fan while in operation.
If you ignore the caution, it could cause
wounding and damage.
WIRIN
G
CHECK
Make sure to check after wiring.
Improper wiring could cause damage.
7
Cooling Tower Parts
Cooling Tower parts are shown below;
 Open Type Cooling Tower
8
[1]
Fan Unit
[2]
Filling
[3]
Spray Filling
[4]
Outside Panel
[5]
Louver
[6]
Upper Basin
[7]
Water Distribution Box
[8]
Inspection Door
[9]
Internal Framework
[10]
Lower Basin Frame
[11]
Lower Basin
[12]
Inspection Board
[13]
Ladder
[14]
Internal Pipe
[15]
Strainer
[16]
Make-up pipe (Auto)
[17]
Make-up pipe (Manual)
[18]
Overflow Pipe
9
Cooling Tower Parts
 Closed Type Cooling Tower
10
[1]
Fan Unit
[2]
Heat Exchanger (Coil)
[3]
Heat Exchanger (Filling)
[4]
Coil Frame (FRP)
[5]
Outside Panel
[6]
Louver
[7]
Upper Basin
[8]
Water Distribution Box
[9]
Inspection Door
[10]
Framework
[11]
Basin Frame
[12]
Lower Basin (FRP)
[13]
Inspection Board
[14]
Ladder
[15]
Header
[16]
Collection pipe
[17]
Spray water Pipe
[18]
Spray Pump
[19]
Strainer
[20]
Make-up pipe (Auto)
[21]
Make-up pipe (Manual)
[22]
Overflow Pipe
11
 Fan Unit
[1]
Fan Casing
[2]
Fan Blade Assembly (Fan Blade + Hub)
[3]
Nose Cone
[4]
Fan Support
[5]
Motor
[6]
Motor Base
[7]
Fan Shaft
[8]
Belt Cover
[9]
Fan Pulley
[10]
Motor Pulley
[11]
V-Belt
[12]
Fan Guard
12
Precaution in cooling tower operation
 Precaution in trial operation
Warning
Do not enter (climb up on) tower while fan is in operation.
There is possibility of serious wounding or death.
DO NOT
ENTER
Caution
Do not stick hand or foreign substance
into fan while in operation.
DO NOT
STICK
CAUTION
There is a possibility of wounding and
damage.
Be aware of abnormality in terms of
noise, vibration, electric current, water
temperature, waterflow.
If abnormality is found, refer to Trouble
shooting (P47) and handle it promptly.
Make sure to check before operation.
WIRING
CHECK
EARTH
WIRE
CONNECT
ION
Improper wiring could cause damage.
Make sure to check that earth wire is
connected. And switch, fuse and wire is
adequate for motor capacity.
Do not do single-phase operation.
Improper
earthing
could
breakdown /malfunction.
cause
the
13
Make sure to check the following.
Open Type Cooling Tower
Check the circulation water flow.
1. Open Valve of Make-up water Pipe (Manual.)
 Fill up lower basin with water until it
overflows through Overflow pipes [1].
2. Make sure that no water leakage can be found
from Lower Basin (FRP) and internal pipes.
3. Prior to introducing water in lower basin, make
sure that Adjust Valve [2] equipped on Upper
Basin is “fully opened”.
4. Once circulation water starts running in , turn
the Adjust Valve up and down until water goes
up to the level indicated by Sticker [3].
Note
 Expected cooling capacity might not be
secured if water level is not kept at proper
level.
5. Before driving Fan, make sure that no abnormal
drift loss can be found from louver side.
Note
 Improper amount of circulating water and misplacing of filling/spray filling may increase water
droplets splashing out through louver.
14
Check the Fan (Motor) operation.
1. Blade tip should not contact fan casing internal.
2. Drive Fan for several seconds and check the rotation direction (clockwise viewed from the top.)
Note
 Fan having anti-clockwise rotation could not secure required air volume for cooling tower.
Rewiring is required.
For 3 leads (3.7 kW and
below)
For 6 leads (5.5 kW and
over) (Direct)
For 6 leads (5.5 kW and over)
(Star-delta)
3. Drive fan continuously.
Note
 If voltage is lower than the rated, current tends to be higher.
4. See if no abnormal noise is coming from fan and motor.
5. Make sure that operating current should not be higher than the rated.
(Refer to nameplate on motor).
6. See if no excessive amount of water droplets is coming out of fan top.
Note


If Fan motor is controlled by inverter controller, add “JUMP” option to inverter controller.
After about 100 hours’ operation, check the tightness of V belt.
(If V-belt is excessively loose, refer to P36 “V-belt tension adjustment.”)
15
Closed Type Cooling Tower
Check the circulation water flow.
1. Open
Valves
for
Circulation
water
(Inlet/Outlet) and for air-purge [1] on header
pipe.
 Water is filled in Header Pipes and Coils
2. Operate Circulation Pumps intermittently.
 Air inside copper coil is pushed out of
air-purge bleeder.
. Note

With a portion of air still remained inside copper
tube, Closed circuit system fails to perform at its
best.

Application of Automatic Air purge bleeder is
recommended.
3. Close Air Purge Bleeder [1].
Note

If air is not fully released, repeat the above procedure several times.
4. Make sure that no water leakage can be found from pipe, joint (KR joint), coil and header.
Check the spraying water flow.
1. Open Make-up water Valve.

Fill Lower Basin with water until overflows
(through Overflow Pipe [1].)
2. Make sure that no water leakage from
Lower Basin is found.
16
3. Before spraying water, make sure to open
Adjust Valve [2] fully.
4. Run Spray pump for a few seconds to see
the rotation direction (Refer to A, for
Rotation arrow.)
Note
 Counter-rotating operation could negatively
affect performance of pump. Wiring of Spray
pump motor should be positive phase.
5. Run Spray pump continuously.
Note
 See if no abnormal sound is coming from Spray
pump.
 Make sure that operating current should be
equal to the rated or below. (Refer to
nameplate on motor). If voltage is equal to the
rated or below, current becomes higher.
 Once spraying water starts running in, turn
the Adjust Valve until water goes up to the
level indicated by Sticker [2]. Expected cooling
capacity would not be secured if water level is
not equal at each upper basin.
Check the operation of Fan (Motor)
Refer to P15, Open Type, “Cooling tower Check Fan (Motor.) Operation”
17
Precaution in starting operation
Warning
Do not enter (climb up on) tower while fan is in operation.
There is possibility of serious wounding or death.
DO NOT
ENTER
Caution
DO NOT
STICK IN
Do not stick hand or foreign substance
into fan while in operation.
There is a possibility of wounding and
damage.
CAUTION
Be aware of abnormality in terms of noise,
vibration,
electric
current,
water
temperature, water flow.
If abnormality is found, refer to Trouble
shooting (P47) and handle it promptly.
Before starting cooling tower after long intermittent, make sure that nothing (that could cause
accident in the future) has happened to cooling tower.
For Open type cooling tower
1. Check bolt connecting each parts is securely fastened.
2. Check fan and V belt.











There should not be any contact of blade tip to fan casing and any foreign substance adhered to blade.
Open belt cover to see if V-belt pieces are in conformity in terms of type, length and number.
Foreign substance such as dust, bird nest should not be found inside Belt cover.
Grease should not be leaked from bearing.
Check V-belt tension.
Fan Pulley and Motor Pulley should be leveled horizontally.
Blade-fixing bolt should not be loose.
Re-tighten blade-fixing bolt after first 100 hour of operation, followed by periodical re-tightening
work once in every 3 years (once in every year for cooling tower operating throughout a year.)
(Required torque is 80Nm for M16 bolt, 55Nm for M12 bolt)
Re-tighten V-belt after the first 100-hour operation. If V belt is loose, please refer to V Belt tension
adjustment Procedure, P36.
Drive Fan continuously to see if no abnormal sound or vibration is coming out. Also check if motor
amperage is appropriate.
Amperage marked should be below the rated amperage of motor.
Note:


Please refer to P36 tension adjustment procedure for V belt tension.
Keep in mind that the excess in electric current may cause decrease in voltage.
18
3. Clean the followings;
(a) Upper basin
Check and make sure spray holes are not clogged.
Note:
Algae and small rocks may disturb smooth spray water flow leaving tower suffering from
deficiency in capacity. Upper Basin Cover is recommended.

(b) Lower basin and Strainer
Refer to P37 to 39 for Cleaning Work.
(c) Strainer for Float Valve
Note






4.
Float-valve equipped in Kuken cooling
tower is pressure-balance type dual ballcock valve (small models may not follow
this specification).
Built-in strainer helps prevent valve-seat
from clogging.
Strainer can be pulled out along with
cylinder by loosening cap [1] with
spanner.
Make sure to clean it before starting
operation.
Malfunction of float valve could cause
shortage/excess of circulation water.
Refer to P41 (Clean Float Valve strainer.)
Strainer can be removed easily by
loosening cap [1] with spanner.
Fill Make-up pipes with water until it
overflows (from Overflow pipe [2].)
19
5. Make sure that Adjust Valve [3] of
Upper Basin is “FULLY OPENED”
6. Once circulation water starts running
in, make sure that water level does not
exceed the level indicated by Sticker
[4].
Note:
If water level exceeds the level, turn
the Adjust Valve [3] up and down until
water goes down to the level indicated
by Sticker [4].
7. Run
Circulation
water
pump
intermittently to push air out of the
strainer [5].
Note:
 FRP strainer has air release hole
on the top. (Air can be released
automatically.) Refer to the sketch
on the right.

For stainless strainer, air can be
released by taking off plug [6].
20
8. Adjust the position of rod [7] with hexagon
screw [8] to avoid entraining air towards
strainer.
Note:
 Water level eventually becomes stable
by operating continuously. This is the
appropriate operation water level.
 Pressure range of Float valve is from
0.049MPa ~ 0.294MPa.
9. Confirm that there is no water leakage from Lower Basin or Pipes.
10. Start Fan operation (Make sure that no abnormal noise is coming from fan.)
11. Inspect on a daily basis.
Note:
 Refer to P28 “Daily Inspection (In season)” for Items being inspected.
 If water level goes down during the cooling tower operation, air entrainment towards strainers
could occur, causing the normal operation.
In order to be secure the make-up performance for the appropriate water level, check the Float
Valve operation in time of Daily inspection.
21
For Closed type Cooling Tower
Note the followings for closed-type cooling tower as well as the information given on P18 (Open type Cooing
Tower)

Again, make sure to let air out of copper coil.
Note :
 Refer to P16 [Check the circulation water
flow.]

Water in lower basin should be at proper level
up to the top of overflow pipe before starting
spray-water pump.
Note:
 Refer to P16 [Check the spraying water
flow.]
 Spray pump might not be able to run
smoothly if silica or foreign substance
(such as sand particles) is piled up in a
narrow gap between casing and impeller.
 Copper coils may not get wet sufficiently
for a while after restarting cooling tower
operation but it will be sorted out
naturally within a couple of days.
 Condition of spare or emergency-use cooling tower should be checked monthly by running fan and
spray pumps (for about 10 minutes.)
*DO NOT dry-run Spray pump.
 Condition of Spray pump (impeller) should be checked by hand-turning prior to power on. In case
pump impeller cannot be turned by hand, follow Pump unlocking Procedure.
Pump unlocking procedure
Before driving Spray pump, complete the following to unlock the pump;
Note

What to prepare : Flathead screw driver (1#) Hammer (0.5 pound)
1. Take off rubber cap [1] with Flathead screw
driver [2].
22
2. Stick in flathead screw driver [2]
through hole on pump cover and fit the
tip into castle.
3. Hit top of the driver [2] several times
with hammer [3] while twisting it
counter-clockwise to unlock.
4. Once impeller starts turning by hand,
rotate it with flathead screw driver [2]
2 or 3 times. (Unlocking process
completed.)
5. Fit Rubber Cap back in the hole
without leaving any clearance.
Note
 Clearance causes water invasion to
Spray pump internal (Could cause
spray pump malfunction.)
23
Precaution during winter care
: CAUTION
SWITCH
OFF
DO NOT touch electric heater even after it was switched off.
Or, you could get burnt.
Note
● Amperage of fan motor tends to mark higher due to the fact that specific weight of air increases as
ambient temp. decreases.
For Open Type cooling tower
For winter time operation, it
recommended to apply electric heater [1]
is
Note
 To install electric heater [1], apply
thermostat to avoid unnecessary temp.
rise.
 Turn
electric
heater
on
after
heat-generating portion has been soaked
in water. (Float-switch or thermostat is
recommended for the system.)
Make sure to do it in order to avoid fire
and burnout of heater
 Scrub and remove scale sticking around
heater surface with wire brush in
cleaning.
The claggy scale blocks the heat release,
causing electric heater [1] burnt and
damaged.
 For more detail, refer to "Electric Heater
for Cooling Tower Application - Operation
Manual".
For Closed Type cooling tower
It is recommended to apply anti-freeze unit to prevent circulation water from being frozen.
To prevent spray water from being frozen, please refer to “For Open Type cooling tower” above.
Note
 If the ambient temperature comes below -5oC, it is recommended to apply heater for aux pump.
 Apply insulation for pipes for anti-freeze unit or aux pump.
To apply anti-freezing agent for circulation water, note the followings;
Note
 Anti-freeze agent may affect tower performance negatively depending on character and
concentration of the agent in water. Exercise care in selection taking this fact into account. (Such
as Specific heat, Specific gravity, and Freezing temperature, etc )
 Concentration Closed
of the agent
water may
happen
be lowered
due
to unexpected mishaps such as
typeincooling
tower
coiltodrain
water
procedure
water-leakage. Check the concentration periodically and replenish if necessary.
24
Closed type cooling tower coil drain water procedure
1. Close Inlet valve [1] and Outlet valve [2] for
Circulation water.
2. Open all Air release valves [3] connected to
coil-header fully.
3. Open Circulation inlet water drain socket [4]
and Circulation outlet water drain socket [5]

Water is naturally drained out.
Note

If Valve is equipped, open it fully.

If water cannot be drained out naturally,
Move to procedure No. 4.
4. Connect compressor to Circulation inlet water
drain socket [4].
Note

Air purge valves [3] and Circulation outlet
water drain socket [5] should be kept closed.
5. Raise pressure up to 0.3MPa with compressor.
6. Open Circulation outlet water drain socket [5]
immediately.

Water inside coil will be discharged.
[5]
7. Repeat No. 5 and 6 again and again to remove
water completely.
Note:

5 times must be enough to discharge water
completely.
[4]
Note:

Air purge valve [3], Circulation Inlet water Drain plug [4] and Circulation Outlet water Drain plug [5] should be
kept opened until water is filled for upcoming operation.

Coil unit is designed to have inclination toward louver (outlet header.)
Make sure to drain from Circulation Outlet water Drain.

Compressed air fails to push water toward drain outlet if drain plug is opened.
25
Precaution in halting
 Precaution in long term out-of operation
For both Open Type and Closed Type cooling tower
Warning
DO NOT
ENTER
Do not enter or (climb up on) tower while
fan is in operation.
There is possibility of serious wounding or
death.
POWER
CHECK
Make sure to power OFF
There is possibility of wounding caused by
unexpected self-start of tower.
Caution
NO
FOREIGN
SUBSTANCE
Make sure that there is NO foreign
substance into cooling tower or pipe.
Foreign substance could cause the
clogging of strainer.
DRAIN
WATER
During the winter season, make sure to drain
whole water from circulation water pipes and
lower basin.
Pipe and Coil can be cracked by freezing.
Therefore, Air purge valve of header, drain
valve, spray pump drain valve should be kept
opened. For more details, refer to Closed type
cooling tower coil drain water procedure (P25)
To keep tower out of operation for long time, proper inspection and maintenance should be carried out
periodically even during the not-in-use period to be ready for upcoming operation.
 Loosen V-belt to avoid deformation and to protect Fan Shaft and Motor bearing from possible
worn-out due to V-belt tension.
 Cover Fan Discharge port.
To start operation after long-time not-in-use period, follow the instructions below.
 Make sure that no loosening of bolt on each connecting portion and no rust appearing on steel parts.
Replace or repair if necessary.
 Check insulation of fan motor, spray water pump, and circulating water pump. The resistance
should be 3MΩ or at 500V megger.
 Also check the followings prior to operation.
 Warning (P7)
 Precaution in trial (P13)
 Precaution in starting (P18)
 Precaution during winter care (P24)
26
Cleaning and Inspection
Warning
DON’T
BREAK
APART
POWER
OFF
DURING
WORK
Products should not be broken apart by
anyone other than licensee.
The malfunction could cause burn, electric
shock and wounding.
Make sure to check that Fan, Spray
pump, Electric heater and others have
been switched off.
If you ignore the warning, it could cause
a burn or electric shock.
During maintenance and inspection
work, exercise care not to swallow
cooling water and not to inhale droplet.
Make sure to gargle and wash hand
after inspection work.
If you ignore the warning, it could affect
your health.
DO NOT
ENTER
MAINTEN
ANCE &
INSPECTI
ON
PROTECT
ION
Other than the purpose of inspection, do
not enter (or climb up on) tower.
If you ignore the warning, you could get
injured.
More than 2 persons are required on duty
for safety reason.
Some parts may accidentally fall down if it
is too heavy for one person to hold. Injury or
damage on product can be expected.
Secure foot space and wear protective on the
top of cooling tower.
If you ignore the warning, you could get
injured.
Caution
NO
FOREIGN
SUBSTANC
E
REPLACEM
ENT
Make sure that there is NO foreign
substance into cooling tower or pipe.
Foreign substance could cause the
clogging of strainer.
Bearing for Fan shaft and motor
bearing are grease-sealing type.
Expected life time of bearings is 20,000
hours. Therefore it should be replaced
approximately every 2 years.
Replace it soon after you hear the
abnormal noise.
INSPECTI
ON AND
CLEARNI
NG
REPLACE
MENT
Inspect and clean upper basin spray holes
and strainer equipped with Lower basin on
occasion.
Clogging of upper basin holes and strainer could
cause deficiency in cooling tower performance
and damage of strainer.
A whole set of V-belt should be replaced
after 8,000 hrs of operation or every year. If
damaged piece of V belt is found (cut or
worn out heavily), change a whole set of V
belt (DO NOT change damaged piece only)
Overuse could cause the deficiency in cooling
tower performance and damage.
Overuse could cause the deficiency in
cooling tower performance and damage.
REPLACEM
ENT
Spray pump for closed type cooling
tower uses mechanical seal inside. As
soon as water leakage is found, replace
it immediately.
Even if water leakage is not found, it
should be replaced every year.
Overuse could cause the deficiency in
cooling tower performance and damage.
Note
 Maintenance and Inspection requires special knowledge and skill. Therefore, contact Kuken
(Details are shown on the back cover page.)
27
 Daily inspection
Item to be checked
Surrounding of cooling tower
Check the following;
 air condition is normal nearby cooling tower, and something to block air flow is not left.
 there is nowhere happened to have higher ambient temp nearby cooling tower.
 abnormal noise or excessive vibration is not found on tower body or pipes.
 there is no water-pool created by water leaked from cooling tower.
Check the following;
Cooling tower internal
Lower Basin
 Circulating water level in lower basin is
appropriate. (Up to top of overflow pipe.)
 Foreign substance such as leaves, plastic bag,
etc is not left in lower basin.
 Circulating water does not change in colour.
 Circulating water temperature and water flow
is normal.
Strainer
 No foreign substance is clogged in strainer
net.
 No large vortex of water can be seen above
strainer.
Float Valve
 Make-up water is replenished automatically when the ball goes down.
 Float valve strainer is not clogged.
Cooling tower top
Check the following;


Water-distribution holes of upper basin are
not clogged.
Foreign substance is not stuck around fan
blade.
Current

Check that amperage of FAN and pump motors as per the rated or below.
28
 Regular inspection
In order to extend the life span of cooling tower, refer to the table below for regular inspection for your
reference.
Warning
POWER OFF
Make sure to check that Fan, Spray pump, Electric heater and others have been switched off.
Could cause wounding and fire.
Open Type cooling tower
PARTS
Item
Frequency
Every 3
months
Item to check
Check point
Means
No breakage, no
deformation, No
rust
No breakage, no
deformation, No
rust
Repairing,
Replacement
Bolt loosening
Bolt loosening
Retightening
B, NT.
Contact us.
Visual
Check
No breakage, no
deformation
No breakage, no
deformation
Replacement
Visual
Check
No loosening
No loosening
Repairing.
Contact us.
Visual
Check
No breakage, no
deformation
No breakage, no
deformation
Replacement
Visual
Check
No sediment, no
flotage
Spray
water
equally through
upper
basin
holes
Cleaning
Visual
Check
Visual
Check
No breakage, no
deformation
Proper
water
level
being
indicated
on
Upper Basin
No breakage, no
deformation
Smooth
air
intake.
No
clogging such as
scale
No breakage, no
deformation
No scale, No
slime
smooth
air/water flow
No deformation
No breakage, no
deformation
Equal
water
level
Replacement
smooth
air/water flow
No deformation
Visual
Check
Appropriate
water level
Appropriate
water level
Visual
Check
Water leakage
No
leakage
Water
being
dirty,
No clogging
No
polluted
water,
No clogging
Cleaning
No breakage, no
deformation, No
rust
No breakage, no
deformation, No
rust
Replacement
Contact us.
Daily
Every
month
Framework
Every
year
Visual
Check
Visual
Check
Outside
Panel
Upper Basin
Others
Cooling
Tower
Spray water
box
Visual
Check
Visual
Check
Louver
Visual
Check
Visual
Check
Visual
Check
Visual
Check
Filling
Lower Basin
Visual
Check
Lower
Basin
Visual
Check
No breakage, no
deformation
Even air flow
No clogging
No breakage, no
deformation
No Clogging
water
Adjustment
Replacement
Cleaning,
Replacement
Replacement
Cleaning,
Replacement
Cleaning,
Replacement
Replacement
Adjusting
Float Valve.
(P21)
Repairing.
Contact us.
29
Frequency
PARTS
Item
Daily
Every
month
Every 3
months
Visual
Check
Every
year
Visual
Check
Visual
Check
Fan Blade
Visual
Check
Visual
Check
Blade Angle
Visual
Check
Visual
Check
Fan Casing
Visual
Check
FAN
Check point
No breakage, no
deformation
No breakage, no
deformation
Contact us
extraneous
material
Clearance
between blades
Bolt loosening
No extraneous
material
No contact
Cleaning
No
loosening
Bolt
Appropriate
blade angle
No breakage, no
deformation
Bolt loosening
Appropriate
blade angle
No breakage, no
deformation
No
Bolt
loosening
No breakage, no
deformation,
bolt loosening,
oil leakage
Abnormal noise
during rotation,
no vibration
Motor
Amperage,
Voltage
Casing,
Terminal
Box
Fixing Bolt
Contact us
Bolt
tightening
Contact us
Contact us
Replacement
Bolt
tightening
Contact us
Replacement
Bolt
tightening
Contact us
Contact us
No oil leakage
Visual
Check
No breakage,
No
deterioration,
No worn out
No slip
No breakage,
No
deterioration,
No worn out
No slip
Visual
Check
Abnormal noise
during rotation,
no vibration
Visual
Check
Visual
Check
No breakage, no
deformation
No slip
No
Abnormal
noise
during
rotation,
no
vibration
No breakage,
No deformation
No slip
Visual
Check
Abnormal noise
during rotation,
no vibration
Abnormal noise
No
Abnormal
noise,
no
vibration
Abnormal noise
Check
amperage
during
operation
No breakage, no
deformation, No
rust
Below the rated
(indicated
on
motor
nameplate)
No rust
Replacement
Bolt loosening
No
loosening
Bolt
tightening
Pulley
Bearing
Means
Visual
Check
Visual
Check
V-Belt
Item to check
No
breakage,
No deformation,
bolt loosening,
oil leakage
No
Abnormal
noise
during
rotation,
no
vibration
No oil leakage
Visual
Check
Shaft
Others
Acous
tic
check
Visual
Check
Visual
Check
Visual
Check
Bolt
Contact us
Replacement
Contact us.
Adjust (P34
～P35)
Contact us
Adjust (P34
～P35)
Contact us
Replacement
Contact us
Adjust (P34
～P35)
Contact us
Adjust (P34
～P35)
Contact us
Contact us
Contact us
30
Frequency
PARTS
Item
Daily
Every
month
Every 3
months
Every
year
Visual
Check
Visual
Check
Ball tap
Accessorie
s
Visual
Check
Visual
Check
Strainer
Others
Visual
Check
Installation
Item to check
Check point
Means
No breakage, no
deformation
Start/Stop
of
making
up
water/ Normal
movement
of
ball tap
No breakage, no
deformation
No problem of
sucking cooling
water through
Strainer
(No
vortex)
No loosening of
Anchor bolt
No breakage, no
corrosion
No cracking on
Foundation
No breakage, no
deformation
Start/Stop
of
making
up
water/ Normal
movement
of
ball tap
No breakage, no
deformation
Replacement
Others
Cleaning,
Replacement
(P41)
Replacement
Cleaning
No clogging
No loosening of
Anchor bolt
No breakage, no
corrosion
No cracking on
Foundation
Bolt
tightening
Replacement
* It varies depending on the specification.
Closed type Cooling Tower
Item
Daily
Heat
exchanger
(Coil)
Every
month
Frequency
Every
Every
3
year
months
Visual
Check
Visual
Check
Visual
Check
Others
Visual
Check
Item to check
Check point
Means
Water leakage
No water leakage
Contact us
No breakage, no
corrosion
No Scale, no silica
No breakage, no
corrosion
No clogging
Contact us
Water leakage
No water leakage
Spray Pump
Cleaning,
Replacement
Replacement
( Replace after
every 8000 hours
operation)
* Other items to check are same as those of motor.
* The above-mentioned items vary depending on the cooling tower specification.
31
 Parts Replacement
Warning
POWER OFF
Make sure to check that Fan, Spray pump, Electric heater and others have been switched off.
If you ignore the warning, it could cause a burn or electric shock.
For Open type cooling tower
Inspection
PARTS
FAN
Item
Every
month
Fan Blade
Every 3
months
Motor
Cooling
Tower
Visual
Check
Inspection
&
adjustment
Expected
lifetime
Inspection
Fan Casing,
etc
Blade : FRP
Hub : Cast Iron
7 years
Cast Iron
Manufacturer's
standard paint
Synthetic rubber
7 years
Casing : Steel
Shaft
: HDG steel,
Epoxy painting,
Un-refill type
Visual
Check
10 years
Casing
: FRP
Support : Steel
Fan guard : HDG steel
Casing
Visual
Check
7 years
Steel or Cast
manufacturer's
standard paint
Bearing
Inspection
Framework
Visual
Check
10 years
HDG Steel
7 years
PVC
10 years
10 years
Framework
Tank
HDG Steel
FRP
Cleaning
Lower basin
Cleaning
Upper
Basin
Cleaning
Visual
Check
Shaft bearing (20,000
hours or aprox. 2 year
operation)
Remarks
5 years
8,000
hours
or
approx.
1
year
operation
Shaft
Filling
Others
Frequency
Visual
Check
Pulley
V-Belt
Every year
iron,
Bearing
(20,000
hours or aprox. 2 year
operation)
Outside
Panel
Visual
Check
5 years
PVC
Louver
Visual
Check,
Cleaning
5 years
PVC
: Steel,
: FRP,
Strainer
Cleaning
Dismantle
and check
5 years
Cover : FRP / Stainless
Steel,
Mesh : Stainless Steel
Ball tap
Cleaning
Dismantle
and check
3 years
Socket : Bronze,
Ball tap : PE
32
For Closed Type cooling tower
Items
Every
month
Heat exchanger
(Coil)
Spray Pump
Frequency
Every
Every
3
year
months
Visual
Check
Visual
Check
Replacement period
Expected
lifetime
10 years
Mechanical Seal : 8,000 hours or
approx. 1 year operation
Bearing : 20,000 hours or aprox. 2
year operation
7 years
Material
Copper tube
Steel or Cast Iron,
Manufacturer's
standard paint
Anti-Corrosion
Note
 Kuken cooling tower comes with Hot Dip Galvanize (350g/m2) applied on steel parts.
 Life span depends largely on Cooling Tower location and operating condition.
Refer to Expected lifetime and replacement period.
Anti-corrosion specification table.
Parts
Framework
Lower basin frame
Fan unit
Header for closed type cooling tower
Kuken standard anti-corrosion specification
H.D.G. (Hot Dipped Galvanised)
Ditto (Including legs)
Ditto (Excluding shaft, bearing unit & pulley)
Ditto (Joint is brass)
Note
 Touch-up paint should be applied on painted parts or equipment (motor, pump) once every 3 to 5
years.
 Kuken standard specification does not include the painting on the Hot Dip Galvanised parts, resin
parts, Stainless Steel parts and Brass parts. Standard color of paint is Munsel N-5. Dirt should be
removed by thinner and wiped off with clothe.
Rust should be removed off steel parts by scratching with sand paper or wire-brush prior to
applying touch-up paint.
33
 Adjustment procedure
V Pulley, V belt Adjust Procedure
1. Loosen Motor base fixing bolt [1] (2 pcs.)
2. Loosen Adjust bolt [2] (4 pcs.)
3. Slide Motor base [3] toward Fan.
4. Remove V-Belt.
5. Hook new V-Belt.
Note:
 Carefully do the V-Belt replacement
work not to jam your fingers.
 Hook V-belt to motor pulley[5], then to
fan pulley [6] (hook to the lowest groove
first, then proceed to the middle and the
highest)
6. Tighten Adjust bolt [2] (4 pcs.)
Note:
 Do not over-tighten V Belt.
7. Slide Motor base toward motor.
34
Surface leveling Adjustment of Fan Pulley and Motor Pulley
1. Check surface level of Fan pulley [2] and Motor
pulley [3] with a straight measure [1].
Note:
 Leveling string can also be used for level
check.
2. Adjust level by screwing/or unscrewing Adjust
bolt [4] (Total 4 pcs.)
Note :
 Fan Pulley [2] and Motor Pulley [3] should
eventually be leveled on surface without
leaving inclination.
 If surface cannot be leveled easily, use
Pulley puller to pull up Motor pulley [3] to
facilitate the work.
3. Repeat procedure 2 until both pulleys are
totally leveled at and on surface.
4. Have Fan Pulley rotated by 180 degrees.
Note :
 Check the level of Pulley again.
(Max. acceptable level difference between
the pulleys is 5mm but try to keep it within
3mm.)
If surface cannot be leveled easily, use
Pulley puller to adjust the level of Motor
Pulley [3].
35
V-Belt tension adjustment procedure
1. Check V-belt tension with tension gauge.

Note :
To check belt tension, tension gauge
should be pressed against V-belt (through
Reading Port.) For more accurate reading,
target the plain, seamless surface found
when belt-seam comes at the opposite of
the Port.
2. Have Pulley rotated (with V-belt) 7 to 9
times.
 V-belt starts to be conditioned on surface
of pulley.
3. Recheck V-belt tension.
4. Adjust V-belt tension by tightening/loosening Adjust bolt.
Note:
 Check and adjust the tension of top V-belt to keep deflection within the standard.
Diameter
Deflection Load
Deflection
φ 1200
13mm
φ 1400
15mm
φ 1600
20N
17mm
φ 1800
19mm
φ 2000
21mm
5. Tighten Adjust bolt to fix Motor Stand.
Note:
 Once again check that Pulley level is certainly within the maximum acceptable level difference.
(Refer to P35)
 Drive Fan motor for 30 to 60 minutes. (New belt usually gets loose after first running.
Therefore, it is required to check belt tension again. It also makes belts fit in Pulleys.
6. V-belt tension should be within value above.
Note:
 Once new belt is applied, belt tension has to be checked after approximately 100 hours
operation and adjusted if necessary.
 If tension is not sufficient, re-adjust V-belt tension.
36
 Cleaning work (Open type cooling tower)
Clean Lower basin and Strainer.
Clean Lower Basin once a month.
Especially when algae or silica appears noticeably on Filling, do the cleaning work
immediately.
Note
 Vortex appearing above Strainer is a warning signal from cooling tower.
Stop operation immediately and clean Lower Basin.
1. Close Valve of Inlet/Outlet water pipes.
2. Close Valve of Make-up water pipe
(Auto.)
3. Open all valves or plugs for drain pipes
to drain out Circulation water.
4. Remove
floating
ball
and
rod
temporarily from Float valve body.
Note
 Cleaning work without temporal
removal of the ball and rod could
cause the damage.
5. Remove Strainer [3].
37
6. Wash away dirt sticking around wire
mesh of Strainer with brush[4]
7. Spray water through louver to wash
away dirt precipitated at the bottom of
Filling toward the centre of Lower
basin.
Note
 Use hose or jet-spray.
8.
Clean Lower basin pit with brush.
 Remove dirt through drain.
9.
Put Strainer [3] back in position.
10. Have rod [2] and float ball connected back on float valve [1].
11. Close drain valve or plug drain.
12. Open make-up water (auto) valve.
 Refill Lower Basin with water.
13. Open all drain valves again when water comes up to overflow level.
 Drain out dirt precipitated at the bottom of Lower basin.
14. Close all drain valves.
 Refill Lower Basin with water again.
15. Close Outlet water valve. Then, start pump.(Open the valve gradually)
Note
 Open valve gradually until required water flow is secured, then run pump for
another 30 seconds.
38
16. Stop Pump.
17. Temporarily try to remove Strainer once it is soaked completely in water.
Note
 The purpose is check clean strainer wire mesh. (Sometimes remaining dirt or scale comes out
after running pump.
18. Open drain valve again.
19. Wash away the dirt around strainer through drain pipes.
20.
Close drain valve.
Note
 Pour water up to overflow level. Then, run
pump.
 Make sure that vortex doesn’t appear soon
after starting pump.
 To go back in operation after cleaning
Filling and Lower Basin, start with the
procedure 14.
If Pump is started with drain valve opened,
strainer can be damaged due to the dirt
accumulated on strainer mesh.
39
Cleaning of Filling.
Note
 Filling and lower basin should be cleaned at the same time.
 Apply highly pressurized water through Louver.
Clean it with appropriate water pressure and volume in order not to damage Filling block.
When scale appears heavily on filling
1. Remove Louver blades.
2. Remove Filling block from Louver side.
Note
 With heavy Pile-up of dirt on surface, filling block tends to be heavier in weight.
3. Have Filling blocks dried naturally.
Note
 Dry for about 2 hours (in Summer time), 5 hours (in Winter time.)
4. Place Filling blocks on a sheet specially arranged for protection, then wrap it.
5. Slap lightly each filling block entirely over the protection sheet to have dried silica come off.
Note
 Slapping without protection sheet may break Filling.
6. Clean the filling block with Highly-Pressurized (jet spray) water. Then put it back where it was.
Note
 If scale cannot be fully removed, use scale-remover.
 To operate cooling tower after cleaning Filling and Lower Basin, follow the procedure from No.
14 in “Clean Lower basin and Strainer”.(P37~39)
If Pump is started with drain valve opened, strainer can be damaged due to the dirt
accumulated on strainer mesh.
40
Cleaning float valve strainer
1. Close Make-up water (auto) Valve.
2. Loose the valve Cap [1] with spanner.
Note
 If air release holes of cap [1] are clogged,
remove foreign substance.
3. Remove Strainer [2].
Note
 Wash away dirt sticking around wire
mesh with brush.
4. Place strainer [2] back in position
5. Fix Cap [1] with spanner.
6. Open Make-up water (auto) Valve.
7. Have Rod [3] go up and down.
Note
 Check the operation of making-up water.
41
 Retaining cooling tower performance
Performance of cooling tower is totally dependent on mutual inter-relationship of factors such as
circulating water flow, inlet and outlet temp., ambient wet bulb temp., air volume, etc. It is not
appropriate to evaluate a tower performance simply by temp. difference of inlet and outlet.
The ideal way of evaluating performance of cooling tower is to focus on outlet temp. by comparing with
that of design condition having rest of the factors(water flow, spraying water flow, inlet temp., wet bulb,
and air flow) completely fixed to be exactly same in figure.
Generally, tower performance tends to be influenced by the factors shown the table below.
Large temp. difference inlet and outlet
Small temp. difference inlet and outlet
High heat load
Low heat load.
Small water flow
Large water flow
Large temp. difference between inlet and wet Small temp. difference between inlet and wet
bulb
bulb
High inlet temp. (*)
Low inlet temp.
* Inlet in extremely high temp. could soften and deform Filling. (Inlet temp. <45oC)

Calculation of make-up water
Volume of circulating or spraying water decreases in due course because of the following reasons:
 Cooling tower is designed to cool water taking advantage of principle of evaporation.
 Water droplets are carried away in open air by strong wind generated by fan (“Drift loss”).
 A part of water must be drained out to keep proper circulation/spray water quality in tower to be
replenished with fresh water as much, “blow-down”.
To calculate make-up water volume, follow the equation below:
(1) Evaporation loss (WE)
kg/h
WE = (tw1— tw2)×L×Cp÷2520
tw1 : Inlet water temperature(oC), tw2 : Outlet water temperature(oC),
L : Flow rate (kg/h), Cp : Specific heat of water (Kcal/kg oC),
2520 : Latent heat incidental to water evaporation (kJ/kg oC)
If the difference between inlet and outlet temp. is 5 oC, evaporation will be approx. 0.83%
according to the above equation.
(2) Drift loss (WD)
kg/h
It varies depending on tower structure and air-flow velocity. Normally it is about 0.3%.
Make-up water (ΔL) kg/h
In total,
ΔL = WE + WD＝ 0.83 ＋ 0.3 ＝ 1.13%
Note:
 Make-up of 1.5~1.7% is recommended in actual operation.
(For reference) Blow-down
The amount required for Blow-down varies depending on amount of pollutant in the air,
amount of make-up water and multiples of concentration of make-up water. Normally it is
about 0.3% against circulation water.
42
 Water quality control
Cooling tower operation with highly-concentrated circulating water causes the negative effect to open
type cooling tower such as corrosion, scale, and slime.
This effect is also applicable to cooling tower operation with highly-concentrated spraying water to
closed-type cooling tower.
The water suitable for cooling tower application is shown below (code JRA-GL-02-1994) for reference
issued by Japan Refrigeration Association (JRA)
[Standard value for circulating water] Value in Round bracket () shows the JRA standard value for
spraying water (closed-type cooling tower)
Standard
Reference
Items
Criteria
pH [at 25oC]
Conductivity [at 25oC] (mS/m)
Chloride ion (mgCl- /l)
Sulfate ion (mgSO42- /l)
Acid consumption [pH 4.8] (mgCaCO3/l)
Total hardness (mgCaCO3/l)
Calcium hardness (mgCaCO3/l)
Silica (mgSiO2/l)
Iron (mgFe/l)
Copper (mgCu/l)
Sulfide ion (mgS2-/l)
Ammonium ion (mgNH4+/l)
Residual chlorine (mgCl/l)
Isolation carbon (mgCO2/l)
Stability exponent
6.5 ~ 8.2 (7.0 ~ 8.0)
80 or less (30 or less)
200 or less (50 or less)
200 or less (50 or less)
100 or less (50 or less)
200 or less (70 or less)
150 or less (50 or less)
50 or less (30 or less)
1.0 or less (1.0 or less)
0.3 or less (1.0 or less)
Shall not be detected (Ditto)
1.0 or less (0.3 or less)
0.3 or less (0.25 or less)
4.0 or less (0.4 or less)
6.0~7.0 (-)
Tendency
Corrosion
Scale
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
Note
 "○" indicates the marked item is a strong influential factor to from corrosion or scale.
 The items listed above are the major factors having tendency for forming corrosion or scale.
 Item and its unit are in conformity of JIS code K0101-1979.Acid-consumption [pH4.8]
is also referred to as Total alkalinity, or M-alkalinity.
[Standard value for make-up water] Value in Round bracket () shows the JRA
standard value for make-up water (closed-type cooling tower)
Items
25oC]
Standard
Reference
pH [at
Conductivity [at 25oC] (mS/m)
Chloride ion (mgCl- /l)
Sulfate ion (mgSO42- /l)
Acid consumption [pH 4.8] (mgCaCO3/l)
Total hardness (mgCaCO3/l)
Calcium hardness (mgCaCO3/l)
Silica (mgSiO2/l)
Iron (mgFe/l)
Copper (mgCu/l)
Sulfide ion (mgS2-/l)
Ammonium ion (mgNH4+/l)
Residual chlorine (mgCl-/l)
Isolation carbon (mgCO2/l)
Criteria
6.0 ~ 8.0 (7.0 ~ 8.0)
30 or less (30 or less)
50 or less (50 or less)
50 or less (50 or less)
50 or less (50 or less)
70 or less (70 or less)
50 or less (50 or less)
30 or less (30 or less)
0.3 or less (0.3 or less)
0.1 or less (0.1 or less)
Shall not be detected (Ditto)
0.1 or less (0.1 or less)
0.3 or less (0.3 or less)
4.0 or less (4.0 or less)
43
Calculation of multiple of concentration and blow-down
Heat-exchange is done by having part of circulating (spray) water evaporated. Thus, the leftover portion
of the remaining water is quite concentrated. The dissolved ratio between make-up water and the
remaining water is called "Multiple of concentration".
To retain cooling tower performance, cooling tower should be operated with water within the limit of
multiples of concentration.
Blow-down and Make-up water is required as per the amount calculated following the equation below.
ΔL : Make-up water (kg/h)
WE : Evaporation loss (kg/h)
WD : Drift loss (kg/h)
WB : Blow down (kg/h)
ΔL = WE + WD + WB
N : Concentration multiple
N = (WE + WD + WB) / (WD + WB)
From the above, following equation is applicable:
WB = [WE / (N-1)] – WD
(1)
ΔL = WE ×N / (N – 1)
(2)
For example, if evaporation loss is 0.83% of circulating water amount, correspondence of Multiples of
concentration (N) and Make-up water (ΔL) is figured out according by equation (2) above
[Multiple of concentration and Make-up water amount]
Concentration multiple (N)
Make-up water amount (ΔL) kg/h
per RT
2
3
4
5
∞
12
9
8
7.5
6
Note:
 It is possible to check Multiples of concentration of circulating and make-up
water by lab analysis. Periodical water sampling is recommended.
Generally, Multiples of concentration is obtained from the following equation applying sodium
ion concentration value obtained from lab analysis.
N = CR / CM
C R : Sodium ion concentration of circulating (spraying) water (mgCl- /l)
CM : Sodium ion concentration of make-up water (mg Cl- /l)
It varies depending on make-up water quality and system.
There are some ways to blow down;



Equip valve for circulating or make-up water pipe and have the valve kept slightly open to let
some water go out.
Let some water go out through overflow pipe during cooling tower operation by making up
water manually.
Install Auto-blow device.
(Kuken under-flow pipe (optional) is recommended to use along with auto-blow device.)
Note :
 Chemical application is also one of the ways to control water quality
(consult chemical supplier for further reference.)
44
 Consumable Parts List
Note
 Contact us after confirmed the serial no. and manufacturing date indicated on nameplate.
No.
1
Consumable Parts
Fan bearing
Parts
Fan P12
Size and Model
Name plate indicated on Inspection Door
[7] Fan shaft
2
V-belt
Fan P12
[11] V-belt
3
Fan Pulley
Fan P12
[9] Fan Pulley
e.g.) 22B3 -> pulley sized 22 inches in dia.
B- type belt ×3 pcs applicable
4
Motor Pulley
Fan P12
[10] Motor Pulley
e.g.) NBK 4B3F -> B type 3 pcs 4 inches
Note) “F” stands for “FLAT” in shape.
“Boss-shaped” if no letter indication
45
No.
Consumable Parts
Parts
Size and Model
5
Motor bearing

Fan Unit (P12)
[5] Motor
Indicated on motor name plate
6
Spray pump bearing

Closed Type
Cooling Tower (P10)
[18] Spray Pump
Indicated on Spray pump name plate
46
For enquiry
 Trouble shooting
The table below is quick reference to use when you encounter cooling tower trouble.
If direct contact is needed for trouble shooting, check the following information beforehand;
 Items to be specified in Nameplate (Especially “Serial no.” (Refer to P5))
 Specify the troubled parts and detailed description of actual trouble
 Contact person
 “Serial no.” of each motor and spray pump indicated on its nameplate. (P8 ~P12)
Trouble
details
Abnormal
sound &
vibration
Electric over
current
Type
Ope Clos
n
ed
Decrease of
circulating
water
Damage to
cooling coils
Check bolts for looseness and
tighten loosened ones.
Adjust the tension.
○
Bolts loosening.
○
○
○
○
Inadequate tension of V-belts.
Contact of fan blade tips & fan
casing.
○
○
Defective shaft or bearings.
Contact us.
○
○
Defective motor.
Contact us.
○
Reverse rotation of spraying water
pump.
Wire correctly.
○
○
Voltage drop.
Check & measure the voltage and
contact power supplier.
○
○
Incorrect setting of fan blade angle
Contact us.
○
○
Defective motor.
Contact us.
○
○
Defective shaft or bearings.
Contact us.
○
○
○
○
○
○
Defective spraying water pump.
Excessive flow rate.
Imbalanced water.
Imbalanced water into cooling coils.
Insufficient air purge out of cooling
coils.
Check strainer & spraying pomp.
Adjust flow rate in specified value.
Clean upper basin. Adjust valves.
Adjust valves.
Purge air out completely out of
coils from purge valve on header.
Remove obstacles for air intake.
Check V-belts.
Improve the remove obstacle for
ventilation.
Improve the remove obstacle for
ventilation.
Contact
the
distributor.
Adjust the tension.
Clean strainers.
Check and adjust make-up water
float valve.
Check drain valve.
○
○
Insufficient air volume.
○
○
Deflected air intake into cooling
tower.
○
○
Recirculation of discharge air.
○
○
○
○
○
○
○
○
Loosened or slip off of V-belts.
Clogged strainers.
Decrease of water level in lower
basin.
Defective drain valve.
Insufficient capacity of circulating
water pump.
Excessive flow rate.
Imbalanced water.
Excessive air volume into cooling
tower.
○
Excessive
drift loss
Countermeasure
○
○
Abnormal
increase of
outlet water
temperature
Cause
○
○
○
○
○
○
○
Insufficient draining in cold season.
Contact us.
Refer
ence
P36
Back
cover
Back
cover
Back
cover
Back
cover
Back
cover
Back
cover
P36
P37
Replace sufficient capacity pump.
Adjust flow rate specified value.
Clean upper basin. Adjust valves.
Contact us.
Install electric heater or inject
anti-freeze fluid. Install electric
heater or inject anti-freeze fluid.
Make sure to open drain valves
and purge valves.
Contact us.
Back
cover
P24
Back
cover
47
Please fill in the form below soon after receipt of cooling tower.
Type
Open / Closed type Cooling Tower Operation Manual
Serial Number
Date of Purchase
DATE/MONTH/YEAR
Distributor and address
/
/
TEL :
Contact us
Should you have any enquiry or something, do not hesitate to contact us.
KUKEN KOGYO CO., LTD.
EXPORT DIVISION
2-39 OHORI-KOEN, CHUO-KU,
FUKUOKA, 810-0051 JAPAN
TEL
FAX
URL
E-mail
: +81-(92)-741-5361
: +81-(92)-715-0891
: http://www.kuken.com/
: export@kukenkogyo.co.jp
48