TABLE OF CONTENTS - INTRODUCTION
I.
Introduction .................................. 2
MZ 25C
Important Information ...................... 2
The Monitor MZ .............................. 3
Technical Specifications ................. 4
Getting Started ............................... 5
Receiving, Opening, Storage ........... 5
II. Installation & Technical ............... 5
Location .......................................... 5
Mounting ......................................... 6
Using MZS to Produce DHW .......... 6
Condensate .................................... 7
Charging & Leak Testing ................. 7
Corrosion ........................................ 8
Freeze Protection ........................... 8
Gas Piping ..................................... 8
Propane Conversion ........................ 8
Venting ......................................... 10
Electrical . .................................... 15
Start Up ........................................ 16
Flow Verification ........................... 16
III. Accessories ................................. 17
BS Indirect Water Tank ................. 17
Domestic Hot Water Kit ............... 18
MZ Mod Control ............................ 18
IV. Maintenance ................................ 19
V. Troubleshooting ......................... 19
VI. Appendix A ................................. 22
Piping schematics ........................ 22
Wiring schematics ........................ 26
VII. Appendix B ................................. 29
Parts and Assembly drawings ...... 29
VIII.Warranty ..................................... 40
I.
I N T R O D U C T I O N
! FOR YOUR SAFETY !
This product must be installed and serviced by a professional service
technician, qualified in hydronic heating system installation and
maintenance. Improper installation and/or operation could create carbon
monoxide gas in flue gases which could cause serious injury, property
damage, or death.
Improper installation and/or operation will void the warranty.
! WARNING !
If the information in this manual is not followed exactly, a fire or
explosion may result causing property damage, personal injury or
loss of life. Do not store or use gasoline or other flammable vapors
and liquids in the vicinity of this or any other appliance.
! WHAT TO DO IF YOU SMELL GAS !
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your
building.
• Immediately call your gas supplier from a nearby phone. Follow
the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire department.
Products that have earned the Energy Star® are
designed to protect the environment through
superior energy efficiency.
ISO 9001 registered. Approved by AGA, CGA,
CSA, IAS, CE and several state and municipal
approvals.
-
I M P O R T A N T
I N F O R M A T I O N
The purpose of this manual is to provide a useful reference for
contractors, distributors, engineers, architects, building
owners, and those considering the use of this heating system.
heat. No other controls or mixing valves are needed for low
temp applications. The MZ’s design simplifies multi-temp,
multi-zone applications.
1. There is no low temperature return limit. This means that
NO SYSTEM / THERMAL SHOCK PROTECTION IS
REQUIRED. The MZ is a fully condensing heating system.
The colder the return water, the more condensing action,
the more efficient.
4. When using the MZ for domestic hot water (DHW) or other
priority application, use our MZ DHW kit, part # 9523. It
makes combining different temps for heat and DHW or
other applications quick and easy. Our 25, 40, 50 and 80
gallon BS tanks are perfectly matched to MZs.
2. The heat exchanger is stainless steel.
5. MZ heating systems are completely self-contained.
Circulator pump, air eliminator, low water cut off, pressure
relief valve, condensate trap and drain, return water strainer,
temperature/pressure gauge, fill/ drain valve, on/off &
summer/winter switch, manual flow bypass, and, except
for the MZ40C, an expansion tank big enough for a 25
gallon system.
•
You will not shock, warp, corrode, or otherwise harm it
with temperature or rapid temperature changes.
•
No primary/secondary piping arrangements are needed
to protect the heating system from low-temp. operation.
•
You can size the heating system to the heat loss of
the structure. This is important when the structure has
been improved over the years but the original radiation
remains, permitting lower operating temps at high
efficiency and comfort levels.
6. Three vent systems available:
1.) Parallel CPVC - separated exhaust & inlet air
2.) Horizontal concentric
3. An adjustable control knob on the unit, from 65º to 176º F,
controls the outgoing water temperature limit for the main
MZ INSTALLATION & MAINTENANCE
3.) Vertical concentric
For most new and retro-residential jobs, there are no other
2
INTRODUCTION
components to buy in order to supply heat to the distribution
system. The MZ is a “mechanical room on the wall.” Labor
savings are dramatic.
8. MZ Heating System facts:
If a system is designed with a run temperature of 180°-200°F,
extra radiation may be needed since the MZ is not designed
for such high temperatures.
7. The MZ is wall hung, zero clearance, and direct vent (uses
no room air). It can be mounted almost anywhere; above
the washer / dryer in the laundry room, in a pantry,
bathroom, closet, kitchen - you name it. Because it has
no footprint, it is extremely valuable in condos and
apartments.
•
Longest successful history of reliability of all high
efficiency, fully condensing heating systems.
•
ISO 9001 certified.
•
Perfect for radiant heating.
•
EPA Energy-star listed.
•
CSA Listed for Canada & US.
The rest of this manual should give you all the information
needed to properly plan, install, maintain and service this state
of the art, ultra high efficiency heating system.
THE MONITOR MZ 25C
Combustion air intake via
concentric flue housing.
Flue gas
outlet.
Extremely
reliable spark
ignitor
Pre-mixing stainless steel burner.
Flame inspection port
(visible from cabinet door).
Air flow proving switch.
27-watt nearly silent air
inlet combustion turbine.
Honeywell® gas valve.
Cast aluminum water jacket.
Heat exchanger exhaust outlet.
Stainless steel finned-tubed
heat exchanger.
Convenient tapping for
flue gas measurement.
Rubber gasket for
cabinet seal
Pressure relief valve.
System water
temperature/pressure indicator.
Adjustable system
water temperature control.
Water proving flow switch.
Electrical interface panel for
thermostat & household power.
Gas inlet pipe.
On/Off switch.
Grundfos®1542 3-speed
circulator pump.
Summer/Winter switch.
Expansion-tank NOTE: Easyoff
expansion tank connection.
(Typical of quick piping
connections and extremely easy
parts access throughout.)
Air Eliminator- NOTE: Air vent
on top is fully serviceable
without need to drain system.
Condensate trap.
Stainless steel fill &
drain ball valve.
Grommets for electrical wiring.
Heating system supply
water outlet from below
(connection in back).
3
System return water inlet
with stainless steel strainer
to prevent clogging.
www.monitorproducts.com
INTRODUCTION
T E C H N I C A L S P E C I F I C A T I O N S
MODEL
MZ25C
MZ40C
MZ25S
BTU input
94,500 (Shown Above)
71,000 / 142,000
94,500
AFUE Efficiency
92 to 97%
92 to 97%
92 to 97%
(depending on return water temp.)
(depending on return water temp.)
(depending on return water temp.)
Built-in Controls
& Functions
Priority pumped hi-temp
circuit (for DHW or heat)
Priority pumped hi-temp
circuit (for DHW or heat)
Intergal DHW tank with
seperate aquastat
Dimensions
30" H x 22" W x 13" D
30" H x 22" W x 13" D
30" H x 22" W x 13" D
Weight
125 lbs.
160 lbs.
160 lbs.
Vent Length
Vent runs longer than 13.5 feet derate input by 1% per 30 feet. Contact MPI if run is to exceed 30 feet.
Fuel (see pg. 12)
Each MZ is factory tuned for natural gas, but propane kit is included. Conversion takes about 15 minutes.
Q U I C K
R E F E R E N C E
Heating value H
60°F / 5.5°C
BTU/foot3
CO/ CO2
Inlet Pressure (IWC)
Gas flow (cf per hour) @60°F
Air Reducer in /mm
Gas Orifice in /mm
P 2 (outlet pressure, IWC)
Air Pressure Switch Differential
Heat Input (BT_U / _HR)
MODEL
NATURAL GAS
LP GAS
MZ 25
MZ 40
BOTH
MZ 25
MZ 40
MZ 25
MZ 40
MZ 25
MZ 40
MZ 25
MZ 40
MZ 25
MZ 40
MZ 25
MZ 40
MZ 25
1075
2500
30ppm / 9.5%
50 ppm / 10.7%
7.0"
11.0"/13"
87.9
132
1.14" / 29mm
None
0.228" / 5.8mm
None
2.8"
2.8"
1.57" IWC
.79" IWC
94,500
Two Stage
71,000 / 71,000 Each
37.8
56.8
1.22"/31mm
None
0.138"/3.5mm
0.165"/4.2mm
5.50"
2.8"
1.57" IWC
.79" IWC
94,500
Two Stage
71,000 / 71,000 Each
MZ 40
MZ 25S Domestic Hot Water Flow Rate
Delta 54 °F (30°C) @ 2.91 GAL/MIN
Combustion Products
MZ 25 SERIES: Max temperature: 176° F (80° C).
Flow rate 32° F (0° C) 14.7 PSI (1013 mbar):
1201 foot3/h - 34 m3 h.
Minimum System Water Flow Rate
MZ 25C and M25S: 3.5 GAL/MIN
MZ 40C 4.25 GAL/MN
MZ 40 SERIES: Max temperature: 176° F (80° C).
Flow rate 32° F (0° C) 14.7 PSI (1013 mbar):
2084 foot3/h - 59 m3 h.
Water Pressure
Heating pressure: maximum 43.5 PSI (3 bars) minimum 14.5 PSI (1 bar)
Hot water pressure: maximum 87 PSI (6 bars)
Water capacity of expansion tank on MZ25C/S
26 gallon system capacity
Maximum Operating Flow Temperature
Nominal 180° F (80° C).
Water capacity of:
MZ25C 1.5 gallons
MZ25S 6.50 gallons
MZ40C 2.25 gallons
Electrical Supply
120V -60Hz -15AMP
MZ INSTALLATION & MAINTENANCE
I N F O R M A T I O N
4
INTRODUCTION - INSTALLATION AND TECHNICAL
GETTING STATED
auto fill valve if one is required or as the appropriate place to
connect additional expansion tank, if needed. If not needed, cap
it. If you are going to use it, check to make sure that the opening
in the male port has been drilled out.
RECEIVING:
Before the contractor accepts the MZ, care should be taken to
verify that it has suffered no shipping damage. MPI cannot cover
shipping damage. Trucking companies refuse to cover hidden
damage if the damage is not claimed immediately.
All of the parts inside the MZ’s cover are important and should be
carefully guarded during the time between unpacking the MZ
and installing it. The gaskets that are part of the connection
kit are easy to misplace. Please put them in a safe place
until ready for installation.
The MZ is externally protected by foam inserts, a plastic bag
and cardboard corner braces. Between the foam protector for
the top of the MZ and the carton is a steel mounting rail that is
formed to match the mounting rail on the back of the MZ.
Combusion air in
OPENING THE MZ:
The front cover of the MZ is sealed against the back with a
rubber gasket. With the cover on, the interior of the MZ becomes
a plenum. The cover is held at the top by a mounting lip from
which it hangs. The bottom of the cover is fitted with two clips
that snap closed around the bottom of the back. These clips are
secured with two screws that hold the clips in place. Remove
the screws so the cover can be removed. Replace them when
the installation is complete.
Products
of combustion out
Concentric flue illustrated here. Pipe must
be extended to outside of structure.
STORAGE:
If the MZ will not be installed right away it should be inspected
and then stored in a secure, dry location.
INSIDE THE COVER OF THE MZ ARE:
• Installation instructions
• LP conversion kit and instructions
• A container of BIONIBAL corrosion inhibitor
• A set of union elbows and gaskets for connecting the MZ
water and gas piping
• Two (2) service drivers.
You will notice that one of the heating systems “J” pipes has an
extra 3/4" male port on it. This can be used for the return of the
Domestic Hot Water or high temperature circuit, as well as an
Combustion chamber
Condensate collection
II. INSTALLATION AND TECHNICAL
CHOOSING A LOCATION:
the MZ’s heat exchanger or be carried into the condensate
trap. Some airborne substances that can be encountered in
the residential and light commercial applications that the MZ
is commonly used in can cause premature failure of
components vital to the MZ’s function. The MZ’s combustion
air must be free of chlorine, fluorine, bromine, acids, cleaning
compounds, solvents, metal dusts, metal fumes and air
contaminated with the gasses produced in animal confinement
buildings.
When choosing a location to mount the MZ, run length of the
venting may be the primary factor, since it has the most limiting
factors and, in the case of the concentric type, it can be
expensive.
The other factors are proximity to existing or proposed piping
and gas lines, as well as a condensate drain. It is usually
easier to run longer piping and gas lines than it is to have a
far reaching and multi-elbowed vent system. The MZ should
never be mounted outdoors open to the weather. A sheltered
outdoor location is OK, but freeze protection of the condensate
trap and drain and of the circulating fluid will be necessary in
cold climate zones.
Take special care to avoid chlorine fumes such as from
muriatic acid commonly used for concrete cleaning. Special
care should be given to MZ installations that are near
swimming pools, laundries, beauty parlors, dry cleaners, metal
working operations, metal treating operations, industrial
plants, automobile or diesel operations, and animal
confinement facilities.
The mounting wall should be sound and dry. Wall anchors can
be used for masonry; screws for wood and carriage bolt for
metal frames. If the wall is stone or very uneven, a pair of 2x4s
from the floor to the ceiling joists works fine. Be sure to leave
clearance for the vent if vent is exiting straight out the rear.
The MZ is very quiet and is rated for zero clearance to
combustibles. It requires no special utility room or fireproofing
for its location. It can be put in living spaces, pantries,
bathrooms or closets. Since it is sealed combustion, it does
not need any indoor air source of any kind though indoor air
Clean combustion air is necessary for proper operation of
MZ units. Some dust will be brought into the MZ and will burn
in the flame. Some of the ash produced will cling to the fins of
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INSTALLATION AND TECHNICAL
for combustion is approved if National Fuel Gas Code
requirements are followed.
Utilizing indoor air can cause a decrease in the overall system
efficiency. The MZ should not be run where ambient
temperatures exceed 125° F.
When the time comes for the heating system, simply
remove the plugs, hang the MZ, tighten the union nuts
that connect the MZ to the piping and fill the unit. Preplumbing spares you the worry (and cash flow) of having
the heating system sit on the job site out of your control
while construction goes on. Thirty minutes should be all
you need from delivery to light off.
MOUNTING THE MZ:
The MZ comes from the factory with a wall mount bracket,
gas and water pipes. With this method you must: Mount the
bracket securely, hang the MZ, attach the included turn-down
elbows and begin piping. Note that when the caps that cover
the nipples on the heating system are removed, it is normal to
find water left over from the test-run firing at the factory. Watch
out for black-water staining if you are working in a clean area.
Always flush the heating system with plenty of clean water
before commissioning.
There are times when the rough piping for the heating system
must be installed and pressure tested before the heating
system is actually needed. The pre-plumbed wall bracket was
designed for this scenario.
Note that the pre-plumbed brackets come with and domestic
cold water shut-off valves on the 25S.
The pre-plumbed bracket (part #9511 for MZ25C pictured at
right, #9512 - MZ40C and #9513 for MZ25S) allows
completion of the heating and domestic water piping without
the heating system present. NOTE: All MZ heating systems
are shipped with an offset “Z” bracket for flush mounting. The
#9515 Spacer Back Plate for MZ25C & the #9516 Spacer Back
Plate for MZ25S and MZ40C allow piping to be run up behind
the unit.
Pre-plumbed brackets can be a big help with radiant systems
on new construction or major remodel jobs. Fit the bracket,
pipe the gas and heat, use standard pipe plugs with the
supplied fiber gaskets to pressure test the entire system.
USING MZS TO PRODUCE DOMESTIC HOT WATER:
a 54º F temperature rise. That is a constant draw of 174
gallons per hour. That setting maximizes efficiency and DHW
production, and works fine for a one-shower application.
SIZING:
As long as the BTU output of the MZ is greater than the design
heat loss of the structure, the DHW draw on the MZ does not
have to be taken into account because DHW run times are
very short. The only time that DHW loads affect sizing is when
they are unusually large.
The tank on the right side of the MZ25S inside its cover holds
system water. A copper fin-tub coil inside the tank transfers
heat from system water to domestic water. The adjustable
aquastat just above and to the left of the tank sets the limit
for the DHW-water temperature. We recommend a setting of
no more than 120°. If the DHW aquastat is set above 145º F
the fixed, manual-reset high-Limit supply-water thermostat
on the MZ may trip, causing nuisance callbacks.
INDIRECT:
Because of its very high efficiency and very quick response
time, the MZ series is especially well suited for high-volume
DHW water production through the use of water storage tanks
using the heat produced by the MZ. Our 25, 40, 50 and 80
gallon stainless tanks are designed with the contractor, the
end-user and the MZ in mind.
The temperature of DHW is independently controlled and
regulated by adjustable settings on the MZ25S. The MZ25S
also includes an adjustable flow setting device for DHW.
In mixed space-heat DHW applications, the DHW function is
given priority over space heat through the use of a three-way
valve or priority pump system controlled to direct 100% of
the MZ’s output to the heat exchanger in the DHW system.
When there is a low DHW flow through the MZ25S, the system
water in the tank will give up heat to the DHW and its
temperature will fall until the aqustat closes. The MZ will add
heat to the tank at faster rate than it is being taken out, and
the temperature in the tank and in the DHW will rise until the
aquastat is satisfied. Then the temperature will start to fall
again until the aquastat calls for heat again. This situation
presents little or no problem for laundry, dishwashing, hand
washing or other common DHW uses.
DIRECT DOMESTIC HOT WATER, THE MZ 25S:
The MZ 25S provides space-heat and DHW at extremely high
levels of efficiency and low levels of pollution. It is especially
well suited for structures in which floor space is at a premium.
The MZ 25S will produce 2.9 GPM of domestic-hot-water at
MZ INSTALLATION & MAINTENANCE
6
INSTALLATION AND TECHNICAL
CONDENSATE:
For steady water temperatures, the DHW water flow rate
through the MZ25S must be high enough to keep the MZ’s
burner on. If the user complains of DHW temperature swings,
especially in the shower, install a thermostatic mixing valve
between the hot and cold legs of the system. Make sure it is
a thermostatic, not a tempering valve. Also make sure that
the temperature setting of the MZ25S is at least 15° above
the desired mix temperature of the thermostatic valve (even
if it means a higher than needed gpm valve is used), or there
may be temperature fluctuations.
Condensate removal can be accomplished by letting it drain
into the building’s normal drain or septic system. The MZ’s
condensate output depends on the return water temperature
of the heating system. Colder return water means higher
efficiency and more condensate. Over time condensate will
eat concrete, iron and copper drains. Most drain water is
alkaline which will neutralize condensate. Percolating
condensate through crushed limestone will neutralize it. If no
gravity drain available, an acid-proof condensate pump will
do the job.
NOTE: The DHW performance of the MZ25S is not exactly
like that of a regular hot water heater, so make sure that you
or your customer understand its limitations. Filling a bathtub
will take longer, since most wide open spigots will not yield
hot enough water for a comfortable bath. The filling process
will have to be slowed in order to keep the temperature up.
Make sure your customer knows this! If space is not critical,
it is almost always better to use an MZ 25C and one of our
BS tanks. The cost of the tank and valves are little more than
the difference between the 25S and 25C. It has been our
experience that those people who choose the MZ25S do so
for the exceptionally high efficiency for overall DHW as
compared to conventional standing-pilot, gravity-vented gas
water heaters, and easily adjust to the subtle differences.
CHARGING & LEAK TESTING:
It is assumed that the system into which the MZ is being
installed is a leak-free system. Leaks in the system will
damage the heating system and void the warranty. If there are
leaks in the system, fresh water will have to be added to the
system to replace the lost water. The addition of fresh water,
over time, will always bring air and dissolved minerals into the
heating system and will dilute the corrosion inhibitor. All of
which will cause a failure.
The proper concentration of BIONIBAL corrosion inhibitor (1%
by volume for all metal pipe systems and systems with oxygen
barrier tubing, 2% by volume for non-barrier systems) that is
shipped with the MZ will completely protect the MZ and the
system it is connected to from corrosion if kept at the right
strength. BIONIBAL does not deteriorate over time or get used
up over time. Additional Bionibal is available form MPI.
Table 1 may be helpful in balancing MZ25S DHW systems.
Table 1
MZ25S
Once the system is properly charged with:
Leaving water Temperatures, Degree F.
Temp
GPM Rise
35 F.
40 F.
Inlet
Inlet
Water Water
T e m p Temp
140
145
125
130
45 F.
Inlet
Water
Temp
135
50 F.
Inlet
Water
Temp
140
55 F.
Inlet
Water
Temp
145
60 F.
Inlet
Water
Temp
-
1.5
1.75
105
90
2.0
2.25
79
70
114
105
119
110
124
115
129
120
134
125
139
130
2.5
2.75
63
57
98
92
103
97
108
102
113
107
123
112
128
117
3.0
3.25
52
48
87
83
92
88
97
93
102
98
107
103
112
108
3.5
3.75
45
42
80
77
85
82
90
87
95
92
100
97
105
102
• Water
• BIONIBAL, or
• Water, glycol BIONIBAL mixture, it should remain stable
indefinitely.
Before the MZ is connected, the piping system should be
filled with clean, neutral P-h water to a pressure of 100 PSI. If
there is no change in pressure after 24 hours, the system
can be assumed to be leak-tight. The system should also be
visually inspected as thoroughly as possible. If any leaks are
found, they must be repaired.
The MZ has a brass, male-hose-thread, fill-and drain valve
operated by a stainless-steel ball valve. We recommend that
the MZ not be permanently piped to the structure’s potable
water system, unless local code requires auto fill. If auto-fill
is installed to the system, our recommendation is that it be
turned off. The flow switch in the MZ prevents low-water firing.
It is normal for heating systems to lose a very small amount
of water over time through valve stems or similar fittings. This
trivial amount of water can easily be replenished during normal
maintenance. There is a clear plastic tube in the MZ that fits
over the nozzle on the air vent and prevents the water that typically
spits out of the nozzle from staining the inside of the MZ.
APPROXIMATE DHW PERFORMANCE OF MZ25S AT
VARYING FLOW RATES AND INLET WATER
TEMPERATURES. ALL TEMPERATURES ARE IN
FAHRENHEIT.
First column gives flow in gallon per minutes.
At any steady gallons per minute (GPM) flow rate, the MZ
will raise the temperature of the inlet water by a specific
amount. That temperature rise is shown in the second column.
On start up, the MZ should be run in the heating mode until
the entire system is brought up to operating temperatures.
Third, and subsequent columns, gives inlet water temperature
rising 5º F increments (top row) and the leaving domestic hot
water (DHW) temperature (remaining rows.)
Do not leave city water pressure on the auto-fill during normal
heating system operation since any system leaks will cause
the Bionibal corrosion inhibitor to be diluted and eventually
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INSTALLATION AND TECHNICAL
eliminated. Oxygen and minerals in the water coming in to
replace the water leaking out will damage the MZ.
CORROSION:
The MZ should be filled with clean, clear, neutral ph water
suitable for drinking. A cleaning solution such as a mixture of
water and trisodium phosphate should be used in any systems
with oily residues. Many chemicals have been used over the
years in existing heating systems that could cause
premature failure of MZ units. It is important that no additives
be used in the system water for the MZ other than BIONIBAL,
which is supplied with each unit.
IMPORTANT: The use of a 2% by volume solution of
BIONIBAL in a radiant-heating system using non-oxygenbarrier tubing will protect the MZ and the system to which it is
connected, from oxygen corrosion. In a system using tubing
with an effective, intact, oxygen barrier or in a hard-piped
system, a 1% solution of BIONIBAL is sufficient. BIONIBAL
doesn’t deteriorate or weaken over time, but should be
renewed if system is drained.
in an easily accessible place. The pipe supplying gas to the
heating system must not cause a pressure loss great enough
to decrease inlet gas pressure below the specified minimum
gas pressure values. (5" of water column for natural gas, 11"
for LP.) After initial start up, check that the pressure tapping
points are properly closed and check the general leak
tightness of the gas circuit. Always purge through the gas
pipe work before initial firing of the unit (in order to get rid of
any particles produced by welding or threaded joints).
The unit and its individual shut-off valve must be disconnected
from the gas supply piping system during any pressure testing
of that system.
EXAMPLE PIPE SIZING TABLE
For gas flow through various pipe lengths and diameters.
(FOR REFERENCE ONLY)
Capacity of pipe for pipe size (ft3/hr)
Pipe length
(feet)
1/2"
3/4"
1"
1 1/4"
10
132
278
520
1050
20
92
190
350
730
30
73
152
285
590
40
63
130
245
500
50
56
115
215
440
75
45
93
175
360
100
38
79
150
305
150
31
64
120
250
Under no circumstances should standard commercial antifreeze solutions be used in the MZ. Most of them contain
corrosion inhibitors that are not approved for use in the MZ.
They will cause heat exchanger failures that are not covered
by warranty. No other additives for lubrication, leak stoppage
or any other purpose can be used in the MZ. To do so will
void all warranty.
FREEZE PROTECTION:
Note: Table above is for natural gas with specific gravity 0.60
with a pressure drop through the gas piping of 0.30" w.c. Refer
to ANSI Z223.1 for additional pipe sizing.
In situations where freeze protection is a necessity. MPI ships
5 gallon quantities of BIONIBAGEL anti-freeze which is
formulated with Bionibal at a concentration that will bring a
50/50 mix of BIONIBAL and water to a 1% concentration of
BIONIBAGEL. If the application does not require a 50/50 mix,
the addition of sufficient BIONIBAL to bring the resulting
solution to a 1% concentration is important, otherwise bacterial
growth and corrosion may take place. In non-barrier systems,
which we discourage, a 2% concentration of BIONIBAL must
be assured. One quart (part # 9526) and 2.6 gallon (part
#9519) quantities of BIONIBAL are available from MPI.
NATURAL GAS TO LP GAS CONVERSION AND
HIGH ALTITUDE ADJUSTMENT:
Note that the addition of glycols to the water passing through
the MZ changes the rate at which the mix absorbs and
releases heat, decreasing its effectiveness as a heat transfer
fluid. Glycols also increase the viscosity of the water, making
it more difficult to pump. These factors can significantly
influence the overall performance of the heating system and
should be taken into account in the system’s design.
2. Reconnect nut and tighten.
3. For MZ25C/S models only: Remove the combustion air
fan by pulling it to the right. Disconnect the rubber air hose
and the wiring. Set the fan aside. Note: The split-ring LP
orifice slips into the burner, as shown below. If it fits loosely,
use the appropriate tool to open the split-ring LP orifice so
that it holds in place.
4. Inlet gas pressure for LP gas must be between 11" and 13"
water column with the heating system running. The MZ40C
requires no gas valve change. The MZ25C/S requires a gas
pressure adjustment from the factory 2.8" water column
setting to 5.5". The adjuster is under the slotted cap on the
gas valve. Turn the adjustment screw underneath the cap
full clockwise and then back off one turn counter-clockwise.
Replace cap. The heating system should then fire, permitting
outlet pressure measurement. Repeat adjustments until the
correct outlet pressure of 5.5" is reached. The final pressure
reading at tap P2 must be taken with the unit running and
the cap reinstalled on the gas valve.
NOTE: Many commonly used,
unapproved corrosion inhibitors CAN DAMAGE THE MZ
AND VOID THE WARRANTY.
MZ
Heating
System
GAS PIPING:
The supply line is 3/4" NPT, and
enters at the lower left side of the
unit as shown.
The gas supply pipe must be fitted
with a 1/ 4 turn stop valve located
MZ INSTALLATION & MAINTENANCE
ÍGas Inlet
Each MZ is supplied with a LP conversion kit. Follow steps
for conversion from Natural gas to LP:
1. Loosen the nut from the gas line/burner junction as shown on
next page (there are 2 on the MZ40C). Insert orifice into gas
line. Note that since there is no natural gas orifice in the MZ40C,
the tightening of the union between the gas line and the elbow
sometimes narrows the opening in the gas line for the orifice.
If that occurs, ream the opening. For MZ40C LP heating
systems, insert orifices before mounting heating system.
8
INSTALLATION AND TECHNICAL
Important note about altitude: Since atmosphere thins
as altitude increases, there is less oxygen available to
support combustion at high altitude. The combustion-air
blower used on the MZ
was designed specifically
for the MZ. Its normal
operating speed is partly
determined by the density
of the air moving through
it. As altitude increases,
the MZ’s blower spins
easier and faster in-
Combustion Chamber
unit pressure
ALTITUDE
ADJUSTMENT
DIAGRAM
creasing the amount of air. The MZ can be used up to 6,000
feet dependinc on vent length of run, aAbove 6,000 feet,
adjustment of the air-pressure switch is necessary.
Gas orifice is located in gas-line side of union. Spray union with penetrating
oil and tap wrench to locate nut on union. Gas line may need to be reamed
to accept LP orifice for MZ40.
Ionization probe
Ignition electrode
Air pressure switch
Air orifice location
Outlet pressure
Air pressure switch
test point
MZ25 Nat. 2.8
MZ25 LP 5.5
MZ 40 Nat or LP 2.8
Pressure
Tap P2
Gas
pressure
regulator
Inlet pressure
must stay within 5”
and 7” WC for
Natural Gas and
11” and 13” WC
for LP gas
Ignition accelerator
Solenoid
Servosystem
Pressure
Tap P1
Air fan
Gas valve
To avoid pressure, remove cap, turn adjustment screw
clockwise to increase, counter clockwise to decrease.
Cap must be on to measure.
blockage is reached where CO does begin to ramp up, a
very small increase in blockage makes a very large
increase in CO. It is best to increase blockage VERY
slowly.) Remove jumper wire from switch. Burner will go
out and CO will begin to fall.
ALTITUDE ADJUSTMENT
1) Fire heating system. Let run for five minutes. Measure and
set CO at 30 PPM for natural gas (50 PPM for LP gas ).
There is a tapping in the vent elbow inside the MZ’s cabinet
just to the left of the flue-gas exit from the MZ for flue gas
measurement. Note that the cap that covers the gas valve’s
adjustment screw must be in place when CO measurement
is made.
4) Adjust air pressure switch VERY, gradually counter
clockwise to the point where the switch closes, which will
then cause the burner to relight.
2) Take cover off of air-pressure switch. With heating system
running, jump contacts so that heating system continues
to fire when switch opens.
5) Unblock blower inlet air.
6) CO measurement should then return to 30 PPM for natural
gas ( 50 PPM for LP.) Check to verify that CO is normal.
3) Very, gradually block inlet air to blower with something light
and stiff, such as a credit card, until CO reads between
500 and 750 PPM. (NOTE: Blocking half of the blower
inlet may raise CO only slightly. As the critical point of
7) Replace terminal cover on air-pressure switch, replace plug
in vent pipe, replace MZ cover. Cycle unit to verify normal
operation.
9
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INSTALLATION AND TECHNICAL
VENT KITS FOR MZ HEATING SYSTEM:
MINIMAL STARTER KITS
MP#
#9501
#9531
The most economical venting location for the MZ is on or near
enough to an outside wall so that the vent box that fits the top
left-hand side of the MZ is within 38" of the final termination
point of the vent run. (see Fig. 1)
Description
Page No.
Horizontal Flue Kit, 1 Meter ................ 12
Use part number 9501 to provide all the necessary parts for
or
the above venting option.
Vertical Vent Kit .................................. 14
HORIZONTAL CONCENTRIC BUILT-UP VENT
SYSTEMS
#9501 Horizontal Flue Kit, 1 Meter ................ 12
#9502 Horizontal Flue Kit, 2.5 Meter .................
#9503 Horizontal 90 ° Elbow ......................... 12
#9504 Horizontal 1 Meter Stick ..................... 12
#9520 Flue Adapter to Plastic Run ................ 12
VERTICAL CONCENTRIC BUILT-UP VENT
SYSTEMS
#9505 Vertical Flue Adapter .......................... 13
#2206 Vertical Through-Roof Terminal 52" long
........................................................... 13
#2203 Vertical 1-Meter Stick ......................... 13
#2202 Vertical 1/2 Meter Stick ...................... 13
#2204 Vertical 45° “L” ................................... 13
#9031 Vertical 25-45° Roof Cooler................ 13
#9032
#9033
#9034
#2205
1. Horizontal Concentric:
36”
Maximum
Fig. 1
Minimum
6” clearance
Overhang is 2.5”
Intake pipe 1”
overhang
MZ Heating System
The MZ’s horizontal vent system can run straight back from
the MZ or right, left, or over the top of the MZ at 90º increments
using the standard vent box mounting procedure. Vents must
slope back to the heating system. A minimum drop of 5/8th
inch per foot of horizontal run must be provided.
2. Vertical Concentric:
For vertical concentric venting, Monitor Products, Inc. kit
number #9505 is required. (see fig. 2).
Fig. 2
Vertical 35-55° Collar, Black............... 13
Pipe Support Ring .............................. 13
Vertical Black-Plastic Ceiling Trim ...... 13
Vertical 90° “L” ................................... 13
17.5” (.44 meter)
Intake adapter
Adapter and gasket
VENTING:
The MZ is designed for direct, concentric venting, although it
can be properly vented in other ways. The MZ is vented in 3
basic ways.
1. Horizontal Concentric
2. Vertical Concentric
3. Separated Exhaust & Inlet Air in 3" PVC
Horizontal vs. Vertical: The final terminal point of the vent
run determines which vent system should be used for the MZ.
THE SYSTEMS HAVE DIFFERENT DIMENSIONS AND
CANNOT BE MIXED. The horizontal system is less expensive
than the vertical system, foot for foot and fitting for fitting. For
vent runs in excess of 30 feet, contact MPI. All length of runs
must be accessible for inspection.
MZ INSTALLATION & MAINTENANCE
MZ Heating System
Once the kit has been installed, the venting can be continued
by way of utilizing different lengths of concentric pipe, 90º
elbows, and 45º elbows. Part numbers & descriptions shown
in Table 1. Vents must slope back to the heating system. A
minimum drop of 5/8th inch per foot of horizontal run must be
provided.
TABLE 1
PART NUMBER
CONCENTIC PIPE LENGTHS
2202
1.65 Feet (. 5 Meter)
2203
3.3 Feet (1 Meter)
2204
Vertical 45°
2205
Vertical 90°
10
INSTALLATION AND TECHNICAL
After the area of termination has been selected use part number
#2206 and install vent termination utilizing support bracket
included with kit. (See Fig. 3)
Fig. 5 9530A
2.5" X 9 Long pipe CPVC
Trim so that reducing
bushing fits snug on
top of box.
Fig. 3
3" Coupling CPVC
3" Elbow, CPVC
4’ of 3" CPVC pipe
3" X 2.5" Reducing bushing
Locking ring
Bi-Directional box
Gasket
• BI-DIRECTIONAL VENT KITS: USE FOR TWO PIPE APPLICATIONS
• ALLOWS FOR 3" PVC VENTING
• THIS ARRANGEMENT CAN BE TERMINATED THROUGH WALL
LEFT, RIGHT, OR REAR
Support bracket
(included with kit)
Termination of a
vertical flue must
provide at least 12
inches (30 cm)
above the roof jack
to the combustion air
intake collar. If there
are two units in the
installation
with
vertical flue systems,
the termination of the
systems must be
separated by 16
inches (40 cm). (See
Fig.4)
Fig. 4
30 cm - 12”
Minimum
40 cm
16”
Minimum
s mmuusstt
3. Separated Exhaust & Inlet Air in 3" PVC
In a situation where it is desirable to route the venting in a nonconcentric fashion, use part #9530A as seen in Fig. 5. This kit
will allow for the exhaust to be piped independently of the
intake.
Drain slope towards inside 5/8” per foot
3" Male threaded apapter CPVC
The venting then can be continued in 3" PVC for intake air,
and 3" CPVC for exhaust air. Termination then can be piped in
a conventional manner. Inlet and outlet should be in the same
wind plane.
The flue/combustion air system piping should be installed
observing the following criteria:
• For vent lengths in excess of 30 feet, contact MPI
• For each 90º elbow used in the flue system, subtract 3.3
feet from the total allowable length.
• For each 45º elbow used in the flue system, subtract 1.65
feet from the total allowable length.
• Horizontal runs of the flue system must pitch down 5/8"
per foot of length towards the heating system to facilitate
proper flue products condensate drainage.
• Termination of a horizontal flue system shall not be less
than 6 feet above walkway. Take care to minimize the
likelihood of flue/combustion air intake blockage. Vertical
flues must intake and discharge above the snow line.
• Do not place the flue terminal less than 3.3 feet from a
ventilation hole or opening in a building.
• Termination should be at least 2 feet above the snow line.
• All flue-piping components must be assembled to
provide an airtight flue/combustion air system.
Inspection hatch screw
9501 KIT FLUE
6%
slope
back to
system.
5/8” per
foot of
run.
Dimensions
Inches
5.43
A
4.33
B
C mini 6.00
2.95
D
2.76
E
2.64
F
mm
138.0
110.0
152.4
75.0
70.0
67.0
Flue gas outlet 2.95”
(PP dia. 75)
Air inlet 4.33”
(PVC dia. 110)
Intake pipe 1”
overhang
11
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INSTALLATION AND TECHNICAL
PVC dia. 110
Dia. 4.33”
Positioning slot
Polypropylene dia. 75
Dia. 2.95”
The MZ can be supplied with a standard length flue,
which can be used to run through a wall up to three
feet thick directly behind the MZ. For greater lengths,
specify with your order.
HORIZONTAL CONCENTRIC VENTING: SHORT VENT RUNS
9051 Horizontal Flue Kit
Intake pipe - slides over exhaust pipe
39.36”
1 meter
This arrangement recommended
for vent runs shorter than 4 feet.
This arrangement can be terminated through wall left, right, or
rear.
This end is final
wall termination
End view
(assembled)
MZ Heating System
HORIZONTAL CONCENTRIC VENTING: UP AND OVER LONG VENT RUNS
9503 Exhaust elbow inside intake elbow
9504 Exhaust pipe inside intake pipe
(cut length as needed)
9520 Adapter and gasket
9501 Still needed for termination
MZ Heating System
DO NOT USE
* Note: Direct connection of # 9503
MZ INSTALLATION & MAINTENANCE
12
This arrangement recommended for vent runs longer
than 4 feet.
Order lengths of 9504 to complete desired vent lengths.
INSTALLATION AND TECHNICAL
9530A KIT FOR 3”
PVC VENTING
3” CPVC Elbow
2.5” x CPVC Bushing
3" X 4’
CPVC Stick
Top of heating
system to Top
of Elbow,
11.75”,
Minimum
2.5” x CPVC Pipe. Trim so that Reducing
Bushing Fits Snug on Top of Box
3" X 3" CPVC TO
PVC Coupling.
Remainder of Flue
can be 3" PVC
Retaining ring Fits Inside of
Box to secure Bushing.
Connection Box
Combustion Air Inlet Bushing. Box to 3" PVC.
Combustion Air Inlet Run Can be 3" PVC.
Gasket Between Box and Heating System
Exterior Wall
Flue gas out
Products of
Combustion Out
Combustion-air In
Cap
18” Minimum
Existing chase used for flue and
intake-air runs (for instance,
chimney, after cleaning).
Continuous 3" PVC run for intakeair is preferred, especially if very
clean chase cannot be assured.
DO NOT USE CHLORINATED
CLEANERS
FOR
CHASE
LEANING!!! Combustion air in.
Flue gas out.
Combustion-air In
Two Foot Minimum,
no Maximum
Foundation Wall
NOTE: Inlet and outlet must be
in same wind plane. Otherwise
they can be any distance above
grade or from each other as long
as flue gas cannot reach inlet and
as long as the entire system
meets the requirements of the
National Fuel Gas Code.
Combustion-air to MZ
Soil or Snow Line
All pipe 3" PVC. Connect to MPI’s accessory #9530
A, separated vent kit.
Flue gas from MZ
CONCENTRIC FITTINGS FOR VERTICAL DISCHARGE VENTING
Polypropylene/PVC Concentric - Vertical
Terminal - For Flat or Sloping Roof
Concentric Fittings
Reference Color
2206
Length
Black 42.5”
I.D.
O.D.
Reference
Angle
I.D.
3.15”
4.9”
2204
45 deg
3.15”
4.92”
(80mm)
(125mm)
(1080mm) (80mm) (125mm)
Useful length under sleeve tile - 16.9 inches
(0.43 m)
2205
Extention - Joint Fitting
Sleeve Tile with
Adaptable Coupling
Reference Length
2202
2203
I.D.
O.D.
19.7”
3.15”
4.92”
(500mm)
(80mm)
(125mm)
39.4”
3.15”
4.92”
(80mm)
(125mm)
(1000mm)
Fastening collar (each flue piece must
be adequately supported.)
Useful length after assy. - 17.7 inches (0.45
m) [2202]or 37.4 Inches (0.95 m) [2203]
90 deg
Reference Slope
9031
9032
O.D.
3.15”
4.92”
(80mm)
(125mm)
9033
Diameter
mm
4.92”
(125mm)
Collare are essential to bear the weight of the
vertical extension.
Polypropylene Ceiling Plate to Cover
Rough Opening
Covering
type
Color
25-45 deg Til
Tile Red
35-55 deg SlateBlack
Shingle
Polypropylene/PVC Concentric Elbow
-joint fitting
13
Reference
Reference
Color
9034
Black
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INSTALLATION AND TECHNICAL
VERTICAL CONCENTRIC VENT
These parts are needed to fit the vertical-vent
system to the MZ. The internal flue pipe that ships
with the MZ is sized for the horizontal flue system
and side-by-side two-pipe vent systems. They are
used with the MZ more often than the vertical,
concentric vent system is. When the vertical-vent
system is used, the MZ’s inner vent pipe must be
replaced with one that matches the size used for
the vertical vent system
9505 Vertical
Flue Adapter
This Pipe
replaces
this pipe
MZ HEATING SYSTEM
9531 Vertical
Vent Kit
9505 (See above) and 9505 (See page 13)
Through-roof terminal
Pipe-support ring
MZ HEATING SYSTEM
Slope Venting Back to System a
Minimum 6% Grade (5/8” per foot)
6” Minimum
4.33” or (138mm)
Intake
Pipe 1”
Overhang
Terminal must exit a
minimum of 18”
above the snow line
mandated by local
code or National Fuel
Gas Code.
MZ INSTALLATION & MAINTENANCE
14
MZ
HEATING SYSTEM
INSTALLATION AND TECHNICAL
Exterior Wall
Part 9503,
Horizontal 90
Degree Elbow
Part 9504, Horizontal
I-meter Stick, Cut to
Length if Necessary
Part 9501, Horizontal Flue Termination Kit, Cut to Length
Products of Combustion Out
Terminal Must Exit at the Depth Above snow Line
Combination Air In
Mandated by Local Codes of National Fuel Gas Code.
Foundation Wall Above Grade
Part 9520,
Flue Adaptor
to Plastic Run
Notes: All flue parts are concentric. They exhaust
the products of combustion through a nominal 2.7”
pipe that is enclosed and supported within a nominal 4” pipe. The 4” conveys combustion air back
to the MZ.
Snow Line
MZ
HEATING
SYSTEM
All flue-pipe connection are gasketed slip-fit. It is
recommended that a lubricant such as soapy water be used to facilitate the slip-fit connection.
The male end of each connection should be inserted into the corresponding female end until it
bottoms out.
All flue components should drain back to the MZ.
The MZ an all of its flue parts are zero-clearance to combustibles.
If the terminal point of the MZ as shown in this drawing is below the local snow line, use appropriate numbers of parts 9503 and 9504 to raise the terminal point. Local codes determine flue
distance above snow line. Always terminate with the terminal end of our 9051. Always terminate
in the horizontal plane. The horizontal system will not work in a configuration in which the terminal end of part 9501 is in a vertical position.
ELECTRICAL:
Caution: The 24 volt transformer supplied
with the MZ is only intended to operate the
heating system components. If zone
valves are being used an auxiliary
transformer of the proper VA rating must
be installed separately. Please see zone
valve manufacturers data sheets for proper
transformer
sizing
and
wiring
recommendations. Attaching zone valves
to heating system transformer will cause
damage and will void warranty.
• Electrical connections and control strategies, including
the summer / winter switch.
The installation must conform to one or more of the following,
as applicable:
A.) Local codes or, in the absence of local codes, the National
Fuel Gas Code, ANSI Z 223..
B.) Canada-CGA B149 installation code and/or local
installation codes.
C.) The National Electrical Code ANSI/NFPA No. 70.
D.) CSA Standard C22.1 and Canadian Electrical Code PZ.1.
ELECTRICAL CONNECTIONS FROM SITE
The heating system, when installed, must be grounded in
accordance with local codes or, in the absence of local codes,
with the National Electrical Code, ANSI/NFPA 70 and the CSA
Standard Canadian Electrical Code C22.1.
The MZ is designed for 120 volt, 60 cycle, three-wire (load,
neutral, and ground) current and draws about 112 watts in
full operation. The electric supply should be from a dedicated
15 amp circuit.
The MZ is easy to wire. Trim the minimum amount of material
from the pyramid-shaped grommets in the MZ’s cabinet so
as to provide a snug fit for all wiring in and out of the MZ. Run
low and high voltage wires through the strain reliever on the
left side of the control panel, through the chase and into the
control panel. Make sure polarity is correct or the unit will lock
out right after lighting.
There are 2 black jumper wires going into 3 terminals to the
left of the high voltage block. From left to right they are T3,
T2, & T1.
Note: If both jumpers are left in place, the pump will run
continuously and the MZ will maintain the aquastat
setting controlled by the adjustable black knob on the
MZ’s control panel.
Jumper position and the summer/winter switch have no effect
on a priority zone, or a Domestic Hot Water call coming in to
the MZ through the wiring harness that is part of the DHW kit.
If you desire constant circulation in the heating (winter) mode
(water moving through the “B” side of the 3-way valve at all
times if MPI’s DHW Kit is used for prioritizing or if the MZ 25S
is used) and the thermostat or heating system control firing
the burner as needed, then leave the jumper in T1, T2 and the
heating system control in T2, T3. Constant circulation has
multiple benefits. We recommend designing for constant
circulation whenever practical.
T
120V-60HZ
T3
T2
T1
N
120V-60HZ
T3
L
15
T2
T1
N
L
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INSTALLATION AND TECHNICAL
To call for burner and pump at the same time, leave the jumper
in T2, T3 and the heating system control in T1, T2.
• Check that the flue outlet and air intake is leak free and
unobstructed.
T
120V-60HZ
T3
T2
Flushing the gas will also have the effect of removing any oxide
particles from the pipes produced during brazing.
T1
N
L
With the heating system’s summer/winter switch in the
summer (sunshine symbol) position, the heating system will
not respond to a call for heat from a space heat thermostat or
other space-heat control.
! AT T E N T I O N !
No attempt should be made to connect electrical
wires to any other location except
1. The indirect hot water storage tank wiring kit,
which plugs into the terminal socket on the right
side of the control panel cluster; and which also
includes strap-on aquastat to be installed inside
the MZ and wired in series with the MZ’s builtin high limit flue and leaving water safety limits.
(See page 18).
2. Two-stage external control of MZ 20-40C.
NOTE: Two-stage operation of the Model MZ40C
is automatic: On a call for heat, both burners fire.
When return water temperature gets to between
9º F to 14º F of the setting on the adjustable
aquastat on the face of the heating system, the 2nd
stage shuts off and the 1st stage runs until the
heat call is satisfied. If return-water temp falls, the
second stage comes back on.
PREPARATION FOR USE/INITIAL START-UP:
• Check for the appearance of the flame through the round
observation window inside the hinged door just above the
controls.
• Check that the installation is filled with water. The water
pressure should equal 12 PSI.
The MZ heating system has two air purge valves, one on the
heating outlet, the other on the domestic hot water heater (25
S model dual-functioning unit).
• Check that the electricity supply is connected correctly:
120 V-60 Hz, with correct polarity.
• Check that the siphon trap is filled with water. Check that
the condensate outlet is connected.
• Make sure the circulator is running. If not, remove cap
covering shaft and manually start. The adjustable domestic
hot water thermostat is factory set on the MZ 25S. If it
becomes necessary to adjust this position it’s
recommended that for energy efficiency the setting be kept
at the minimum water temperature consistent with the
consumer’s needs. The maximum DHW temp is 145°. Keep
in mind there is a hot water scald potential if the thermostat
is set too high.
COMMISSIONING:
When operating the unit for the first time, the installer must
verify:
• That the gas valve works properly;
• That the flame control works properly;
• The burner setting: CO, CO2, and gas valve settings
are correct.
1. Open the manual valve on the gas inlet.
2. Switch on the main heating switch, or circuit breaker.
Should overheating occur or the gas supply fail to shut off,
turn off the manual gas control.
3. Set the lighted on/off switch on the control unit to the “on”
position.
Do not use this unit if any part has been under water.
Immediately call a qualified service technician to inspect the
unit and to replace any part of the control system or any gas
control, which has been under water.
4. Put the circulating pump switch to the “winter” position
(snowflake). In the “summer” position (sun), the circulating
pump only works when the domestic hot water tank
requires heating (MZ 25S or C models with indirect hot
water storage tank).
Before initial start up of the unit, the installer should:
• Check that the gas circuit is leak free.
• Carefully flush out the gas pipes. Where the installation is
new, the purge serves to evacuate the air that is contained
in the pipes so that the unit has sufficient fuel. The presence
of air in the gas prevents the burner from lighting and results
in the flame control unit safety device cutting in. This applies
to a new installation running on either natural gas or LP.
For the latter, the storage tank must also be properly
flushed before initial start up.
FLOW VERIFICATION:
In order for the MZ to function properly a minimum amount of
water must flow through the MZ’s heat exchanger to remove the
heat being produced. There is a flow switch inside the MZ that
will not allow the MZ to fire unless there is minimum flow.
Approximate external feet of head available from the Grundfos
UPS1542 in the MZ25 series heating system at flow rates shown.
ATTENTION! All necessary safety precautions should be
taken when venting the gas.
MZ INSTALLATION & MAINTENANCE
16
GPM
3.5
4
6
Speed 3: FT of
Head Available
12
10
5
INSTALLATION AND TECHNICAL - ACCESSORIES
The pump in the MZ40C is generally not capable of pumping
normal heating zones outside the heating system. Such
applications normally will require additional series pumping or
a primary-secondary layout. The pump WILL supply adequate
flow for proper operation of one of our BS indirect tanks through
our DHW kit.
When the MZ is properly connected to a primary-secondary
pumping layout, the MZ’s pump will provide the necessary
flow. When the MZ is directly connected to a system in which
the pump inside the MZ is used to pump the entire system,
the system must be checked for proper flow.
If the system is a single-zone system or a multi-zone system
balanced with manually set circuit setters, there either will or
will not be sufficient flow to close the flow switch. If the system
is multi-zone with zone valves used to open and close zones
on demand, the system can be checked for proper flow by
running the system one zone at a time with all of the other
zones off.
If any of the zones restrict flow so much that the flow switch
will not close, adjustment to the system will have to be made,
such as wiring the system so that the restricted zone can
only operate when another zone is running or adding a pump
to that zone, increasing the pipe diameter or zone valve
selection for that zone, or installing a differential pressureoverflow valve.
LEAVING WATER LIMIT-SWITCH FUNCTION
There is a manual reset high temperature limit switch in the
water jacket of the MZ. In systems with low flow or systems
with water-glycol mixes, it is possible for that manual reset
switch to trip before the call for heat has been satisfied. In
order to check for this possibility, the system should be run
with the adjustable limit switch on the MZ’s panel turned full
clockwise. The temperature - control devices in the system
(thermostats, aquastats etc.) should be adjusted to deliver
the highest temperature that this application will require until
those temperature-control devices are satisfied.
NOTE: If the system has been designed to require high
temperature (>176° F.) water at design conditions, care must
be taken to prevent nuisance trips of the MZ’s manual-reset
high-limit switch. The best ways to do that is to provide for
constant circulation in the winter mode, or add more radiation.
In multi-zone applications, each zone should be run
individually to assure that nuisance limit-switch trips will not
occur during the heating season.
If the manual reset switch trips, pull the adjustable-limit switch
knob and adjust the wire stops in the knob so that the
adjustable limit shuts the MZ down before the over-limit switch
opens. If the leaving-water temperature at that setting will
satisfy the structure’s need for heat on a design day, the
problem has been solved.
If the leaving-water temperature will not satisfy the need for
heat at that setting. Changes to the distribution system, piping
arrangement, pumping provision, control system, or the
addition of radiation may be appropriate. Do not install MZ
heating systems in jobs that require more than 176º F. water.
I I I . A C C E S S O R I E S
BS INDIRECT
WATER TANK
A. 316 L austenitic
stainless steel coil.
B. 316 L austenitic
stainless steel tank.
C. Molded, rigid
removable insulation.
D. Removable ABS
plastic casing.
E. DHW cold inlet.
F. DHW hot outlet.
G. Heating system
circuit inlet.
H. Heating system
circuit outlet.
I. Pressuretemperature relief
tap and/or DHW
recycling circuit
tap.
J. Inspection opening
and anode access.
K. Thermometer.
L. Aquastat.
BS50
BS 80
BS 25
BS 40
Models
50
80
25
40
Nominal Storage
Gal.
45.3"
63"
27.5"
36.4"
Height
IN.
23.6"
23.6"
23.6"
23.6"
Diameter
IN.
3/4"
3/4"
3/4"
3/4"
All Pipe Connections
MPT
100
100
100
100
Max DHW Pressure
PSI
68-176ºF
68-176ºF
68-176ºF
68-176ºF
Aquastat Range
F
10.8ºF
10.8ºF
10.8ºF
10.8ºF
Aquastat Differential
F
3.9"
3.9"
3.9"
3.9"
Inspection Port Opening
IN.
200
210
MBH
115
115
Nominal Exchanger Power (170ºF Av. system Water Temp)
12
17
MIN.
10
15
MZ25 Nominal Reheat Time from 50ºF to 140ºF Stored
3.8
6.5
6.7
GPM
3.8
MZ25 Continuous Output at 110ºF
260
430
465
GAL.
250
MZ40 Nominal First Hour Draw at 70ºF Rise
86
121
159
LBS.
71
Dry Weight
Ratings assume cold-water inlet at 50ºF, heating system circuit average temp of 170ºF and heating system output at least
equal to the nominal heat exchanger power shown above. Tank output cannot exceed heating system output.
17
www.monitorproducts.com
ACCESSORIES
DHW KIT-MPI #9523
• Rapid way to offer two
temperatures
• Priority to DHW Zone
MZ Heating System
built-in control feature that allows the non prioritized spaceheat side to be regulated by the main temperature knob and
the high temp side controlled by a strap-on aquastat.
The kit contains a factory wiring harness, 3-way valve, motor, and
strap on aquastat. The heating system output’s first connection
is the “AB” port of the 3-way valve. All system water flow thru the
“B” port will be controlled by the MZ’s main temp knob and the
heating thermostats. The “A” port will be the primary hi temp
circuit for DHW recovery. The “A” port is also a priority zone.
Wire the aquastat in series with the high limit on the MZ’s
water jacket. Strap the bulb to the leaving water pipe just
behind the combustion- air fan. Cover with foam insulation.
Secure with nylon ties; not ultra tight. Adjust leaving water
temp. at 170º to 175º F. Scratching the paint off the water
pipe will give a more accurate temp reading.
From Factory
Harness
To 3-way
valve motor
Either black to
Black
Either black to
#2 on BS tank
Brown to
#1 on BS tank
Orange to
Heating System Ground
Monitor’s domestic hot water kit (part #
9523) allows for the zoning and control of
any indirect tank, or any two or more
temperature applications - one usually
being DHW recovery - with the higher temp
being a priority. This system utilizes the
To Indirect tank or
High temp thermostat
Brown
Grey to
Blue
Green
Ground terminal
on tank
(connect to ground)
Red - not used
Red - not used
MPI #9110
MZ MOD CONTROL / MPI #9110
The MZ Mod Control comes with modulating control, 2 strap
on sensors, instruction manual, outdoor sensor, & wiring
harness.
MZ MOD CONTROL SPECIFICATIONS
Control — Microprocessor PID Control. This is not a safety (limit) control
Enclosure — Enclosure D, back Noryl Plastic
Optional Devices — Universal Sensor
Dimensions — 4-3/4" H x 2-7/8" W x 1-7/8 D (120 x 74 x 48 mm)
Approvals — CSA C US, meets ICES & FCC regulations for EI/RFI
Power Supply — 24 V 50/60 Hz 75 VA
Pump / Stage 1 Relay — 120 V (ac) 5 A 1/6 hp, pilot duty 240 VA
Stage 2 Relay — 120 V (ac) 3 A 1/6 hp
Alarm Relay — 24 V (ac) 3 A 1/6 hp
Ambient Conditions — Indoor use only, -40 to 140º F (40 to 60º C) <90% RH non-condensing
Sensors Include — NTC thermistor, 10 kW @ 77º F (25º C 0.2º C) B = 3892 2 of Universal Sensor and 1 of Outdoor Sensor
Control Features:
• Versatile, easily adapts to all common piping methods.
• Heating system inlet and outlet sensors
• Optional primary loop sensor
• Optional DHW sensor.
• Smart control feature can adapt to the building.
• Exercising of heating system pump.
• Purging of heating system based on time.
MZ INSTALLATION & MAINTENANCE
• Display of temperatures & run times
• Error messages for sensor failure with alarm signal.
• Minimum on and off delays
• Adjustable differential.
• Smart control feature adapts to each heating system.
• Built-in test sequence.
• Building occupants can be locked out of installer’s settings.
18
MAINTENANCE - TROUBLESHOOTING
I
V. M A I N T E N A N C E
MAINTENANCE CONSIDERATIONS
MAINTENANCE PROCEDURES
The MZ is an extraordinarily durable and well-designed heat
source. It is built in the same manner as a fine boat or airplane.
While there are parts of the MZ that will eventually wear out,
they are easily replaced. The heart of the MZ, the heat
exchanger, is made of high-grade stainless steel and will last
for many, many years of normal service. Premature failure of
the MZ’s heat exchanger can be caused by the ingestion of
contaminant’s in the combustion air, the use of very hard, very
acidic or very basic water in the MZ, or continuous addition of
water to the system.
In order to minimize no-heat calls other than those that are the
unavoidable result of rare events such as a lightning strike or the
failure of one of the mechanical or electrical components of the
MZ, we recommend that the MZ be given an annual clean-andcheck. The few drops of water that will normally leak out of a
system over time can easily be replenished during maintenance.
If the MZ is not cleaned and checked regularly, there will
eventually be an interruption in the function of the MZ due to
one of the following, easily remedied events:
1) The air-pressure switch will not open due to a reduction in
airflow through the MZ due to an accumulation of dirt on the
inlet side of the combustion-air fan, the accumulation of dirt
in the burner, the accumulation of ash on the heatexchanger’s fin tube or the accumulation of ash in the
condensate trap.
2) The interference with ignition due to flame erosion of the
igniter rods.
Annual service will bring the chance of nuisance no-heat calls
to near zero.
(Approximate time, 15 minutes.)
1) Disconnect plastic tube at top of fan. Grasp plastic nozzle
that connects fan to the burner with right hand. Rest left
hand on combustion chamber and pull fan to right. Fan will
slip off of burner. Disconnect fan wiring connector and set
fan aside.
2) Disconnect plastic hose, igniter wire, flame-proving wire
and ground wire from burner top. Open union in gas line at
burner top. Four bolts secure clips that hold burner to
combustion chamber. Remove front clips. Loosen bolts and
rear spin clips so that burner can be removed and remove
burner.
3) Using plain water, wash heat exchanger fin-tubes. Water
will run out through condensate trap. Unscrew bottom half
of condensate trap. Check trap for accumulation of ash/
mud and clean if necessary. Fill the trap with water and
replace it.
4) Inspect flame proving rod and igniters. Replace if worn. Regap igniter according to specifications in the Technical
Instruction packed with heating system. (2.25 mm, 0.09
inches.) Brush or vacuum burner face. If vacuum is at hand,
vacuum burner outlet. Check fan inlet for dirt on blades and
clean if necessary. Re-connect burner, hoses, wiring, and
fan.
5) Fire MZ, check safety limits and CO and/or CO2 according
to values in installation instructions.
V. T R O U B L E S H O O T I N G
QUICK TROUBLE-SHOOTING GUIDE FOR MZ time, make sure that heat exchanger is not dirty. Inspect
venting to insure compliance with installation instructions.
HEATING SYSTEMS:
! W A R N I N G !
Only trained HVAC service people should do MZ
troubleshooting. The MZ is fed by an electrical current
source that could electrocute. Take care to avoid shock.
Wear safety glasses!
Make sure that the MZ has power, gas, that there is water in
the heating system and that there is a call for heat. Check all
visible hoses and wiring inside the MZ for integrity and good
connection.
Is pump running?
Toggle on-off switch. Water pressure will change when pump
starts. If no change, remove cap from pump end. Rotate shaft
with screwdriver. If shaft rotates freely, check power to pump
(CAUTION, 110 VOL TS). If no power to pump, check pump
relay and associated wiring.
Fan runs but MZ doesn’t try to fire?
Check for air-pressure-switch operation with voltmeter. If
switch does not close, check for blocked flue, blocked
condensate trap or drain. If MZ has been in service for a long
Is water-flow switch closing?
Disconnect flow-switch wiring-harness. Jump connections
back to MZ. If fan runs with connections jumped, most likely
cause is low system water flow. Check for stuck valve,
obstruction in piping, strainer or pump vanes clogged, etc.
Use ohmmeter to check for flow-switch operation. Switch
closes at 3.52 GPM for the MZ25 and 4.4 GPM for the
MZ20-40.
Does the MZ try to fire?
Gas valve and spark normally act simultaneously about 20
seconds after air pressure switch closes. If attempt to light
occurs, but no flame results, (flame failure), the ignition module
will lock out, the fan runs continuously, and power has to be
interrupted before another attempt to light will occur.
Is combustion-air fan running?
If pump runs and flow switch closes, combustion air fan should
run. If not, verify call for heat, check that operating limit is not
satisfied and that manual reset fixed high-Iimit switches are
not open. If fan does not run, check fan power (CAUTION,
110 V.). If no power, check fan relay and associated wiring.
19
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TROUBLESHOOTING
Is there flame failure?
Likely flame failure causes: bad gas-air mixture (too little or
too much gas), no spark, reverse polarity or poor ground.
Check spark by looking up into sight glass at sharp angle.
Check for proper gas pressure with manometer. Check power
for grounding and polarity with volt-amp meter. Check ignitor
electrode gap.
Proper gas-air mixture plus spark equals ignition. If you don’t
have ignition at this point, re-check everything.
When you realize that the MZ is a heating system that requires
nothing more than certain occurrences in sequence to operate,
troubleshooting becomes very straightforward. There are no
circuit boards (other than what may be in the Honeywell flame
control module), only a few relays that dictate exactly what
the MZ is doing, and if it not working, what it needs to do.
PROBLEM
Here is the sequence of events that occur during normal
operation:
1. Power on to the unit
2. Call for heat - both T1, T2, & T2, T3 circuits must be closed
or there must be a DHW or other priority call.
3. Adjustable limit, leaving water and flue limit switches
closed.
4. DHW aquastat closed if priority call.
5. Fan full speed.
6. Pressure differential switch must close.
7. Gas valve open, spark.
8. Flame module proves flame and keeps gas valve open
until high limit is reached, DHW aquastat is satisfied or
call for heat is over.
Other than those sequential steps, there is nothing else that
affects the MZs operation. Here is a troubleshooting chart:
POSSIBLE CAUSE
REMEDY
MZ not running. 1. Power turned off, breaker off.
Power switch
not lit.
1. Restore power.
Power on,
nothing
happening.
No heat or
hot water.
1. Check for high limit trip on top of heat
exchanger or where flue exits at bottom.
2. Check that adjustable operating limit is closed.
3. Make sure there is a call for heat or hot water.
4. Transformer failed.
5. Make sure pump is running (this can be done
by feeling for vibration or turning switch off and
on and watching for movement in the pressure
gauge).
1. Push to reset. If this occurs regularly, see below.
2. Check thermostat, jump T1, T2 & T2, T3. Make
sure switch is on winter (snowflake)
3. Check wires
Call for main
heat or priority
heat has been
verified. All
limits are
closed. No fan.
1. No water flow through the unit. Not enough
flow to satisfy switch. Air in the system, or
return water strainer clogged.
2. Obstruction to flow outside MZ (such as stuck
zone valve).
1. Jump red & orange wires to flow switch. If unit
starts and runs normally, either flow switch is bad
(unlikely) or there is no or low flow.
2. Find and clear flow obstruction. To clean strainer,
remove large nut behind fill/slash drain valve and
pull out strainer. Clean or replace.
Pump is
running, fan is
running, unit
won’t fire.
Check position and integrity of tubes at air pressure
switch. Make sure that tubes are not cut anywhere.
Long tube from fan should see greater than 1.9
inches of water column and should be connected
to + (plus) port on switch. If p is less than 1.9, clean
and check fan.
If the pressure difference between the tube from
the fan and the tube from the combustion chamber
is greater than 1.6 inches of water column (IWC)
for the MZ25 or greater than .9 IWC for the MZ40,
the switch should close.
If pressure switch is OK, after blower has reached
full speed, switch should close. About 20 seconds
later, gas valve should open (loud click) and spark
should commence (spark visible through sight glass
when viewed at sharp angle from below).
Listen for click for gas valve relay after fan has
reached full speed. Watch for spark thru glass in
chamber. (If there is no click or spark, remove the
short clear hose from the black pressure switch. If
the unit fires, the venting is restricted. If no change,
jump the switch. If unit doesn’t fire after 30 seconds
of full speed fan operation, replace Honeywell control
unit. If there is a click but no spark, test for 110 volts
to spark transformer. If there is voltage, test for high
voltage with spare igniter. No high voltage, replace
transformer. If there is high voltage, replace igniter.
If the gas valve clicks and the igniter sparks, remove
P1 on the gas valve a make sure there is gas to the
unit.
MZ INSTALLATION & MAINTENANCE
20
4. Check for voltage on 24V side, replace if none.
5. Check for power to pump with tester and / or listen
for second relay from left to engage when power
is on. If there is power but no movement, remove
the silver slotted screw from the pump body and
turn the shaft manually. If the pump starts, replace
the screw. If it turns easily, replace the pump.
TROUBLESHOOTING
PROBLEM
POSSIBLE CAUSE
REMEDY
Unit fires
normally and
shuts off
intermittently,
fan still running.
Relays chatter
intermittently.
Intermittent signal to T3-2 or T2-1.
Possible loose connection / poor
connection inside or outside of MZ.
Transformer in MZ overloaded by being
used to drive external devices such as
zone valves. Honeywell control unit
failing.
Correct wiring. Isolate zone controller from unit with relay,
or change end switch location to 0 voltage dry contacts.
Check wiring connections. Replace control.
Unit fires
briefly then
shuts off.
Polarity incorrect at terminal, air in
system, gas pressure too low.
Reverse line / neutral wiring. Cycle unit to remove air and / or
add more water. Increase gas pressure - if using propane,
make sure conversion done properly.
Heating System
makes hot
water, but no
heat.
Summer / winter switch on summer, no
call for heat, no flow or not enough flow
in heat zone(s), air in heat zone(s). 3-way
valve stuck.
Switch to winter (snowflake), jump T1, T2 & T2, T3; jump
flow switch as directed above, remove air. Check for
movement of white tab on 3-way valve. For dhw, tab should
be toward valve body, for heat it should move away. Remove
valve motor by releasing pin at base and rotating 1/8 turn.
Manually check for smooth movement of plunger. If it sticks,
remove and clean or replace.
Gas pressure too high, mixture too rich.
Check inlet (P1) and outlet (P2) gas pressures. “means IWC
means inches of water column.
For natural gas, MZ25, P1 5 to 7"; P2 2.8".
For LP, P1 11 to 13", P2 5.5".
For natural gas, MZ40, P1 5 to 7", P2 2.8".
For LP, P1 11 to 13", P2 2.8".
Pressures must stay within the above ranges when firing
and when not.
Unit noisy and
popping; locks
out easily with
fan running.
Gas pressure too low, intermittent gas
service, low on propane, improper
propane conversion.
Same as above.
Unit trips heat
exchanger high
limit regularly.
1. DHW setting too high, temperature
knob too high, abrupt Shut-off of
system at high temperature
2. Strainer and/or pump clogged
1. Lower settings, do constant circulation, increase heat
distribution means.
Unit noisy
during start-up
and operation
rumbles and
vibrates.
2. Lower temperature settings in structure, add radiation,
and / or increase pumping rate.
21
www.monitorproducts.com
Radiant Heat
MZ INSTALLATION & MAINTENANCE
22
VALVE
PURGE/DRAIN
Domestic
Hot Water
SCALE
SIZE
FSCM NO.
DWG NO.
SHEET
REV
VALVE
PURGE/DRAIN
SCALE
SIZE
FSCM NO.
DWG NO.
SHEET
REV
MONITOR PRODUCTS, INC.
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
MONITOR PRODUCTS, INC.
BALL VALVE
1
2
Top view of BS Tank
3
4
System Return
System Supply
I . A P P E N D I X
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
Radiant Heat
BS Tank
(recirc when used)
Relief Valve
3 Way Valve
(Kit # 9523)
MZ Heating System
V
BALL VALVE
Radiant Heat
MZ Heating
System
Radiant Heat
APPENDIX A
A
3 Way Valve
(Kit # 9523)
23
Radiant Heat
BALL VALVE
SCALE
SIZE
FSCM NO.
DWG NO.
SHEET
REV
VALVE
PURGE/DRAIN
SCALE
SIZE
FSCM NO.
DWG NO.
SHEET
REV
MONITOR PRODUCTS, INC.
Outdoor Sensor
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
System Out Sensor
MONITOR PRODUCTS, INC.
System In Sensor
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
MZ Mod Control
VALVE
Domestic
Hot Water
1
2
System
Supply
Top view of BS Tank
System Return
3
4
(recirc when used)
Relief Valve
MZ Heating System
PURGE/DRAIN
BALL VALVE
MZ Heating
System
Baseboard
APPENDIX A
www.monitorproducts.com
Zone 3
Zone Valve (TYP)
Relief Valve
(recirc when used)
System Return
System Supply
Domestic
Hot Water
Top view of BS Tank
3
4
1
2
MZ INSTALLATION & MAINTENANCE
BS
Tank
Expansion Tank & Air Separator (May
be Required due to System Capacity)
24
VALVE
PURGE/DRAIN
3
Domestic
Hot Water
1
2
SCALE
SIZE
FSCM NO.
DWG NO.
REV
SHEET
VALVE
PURGE/DRAIN
BALL VALVE
Top view of BS Tank
System Return
4
System Supply
SCALE
SIZE
FSCM NO.
DWG NO.
SHEET
REV
MONITOR PRODUCTS, INC.
BS Tank
(recirc when used)
Relief Valve
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
Zone 2
MONITOR PRODUCTS, INC.
MZ Heating
System
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
Air Vent (TYP)
BALL VALVE
Zone 1
3 Way Valve
(Kit # 9523)
MZ Heating
System
Air Handler
APPENDIX A
BALL VALVE
Storage Tank
MZ Heating
System
REV
SHEET
DWG NO.
FSCM NO.
SCALE
SIZE
PURGE/DRAIN
Zone 2
VALVE
MONITOR PRODUCTS, INC.
Heating System
Supply
3 Way Valve
THIS DRAWING IS FOR REFERENCE ONLY. IT
IS NOT INTENDED TO DESCRIBE A COMPLETE
SYSTEM. EACH SYSTEM SHOULD BE DESIGNED BY A PROFESSIONAL.
APPENDIX A
Heat Exchanger
for Pool Heat or
Snow Melt
Radiant Heat or other
Low Temp Heat
Chiller
BS Tank
TWO-TEMP SYSTEM WITH SINGLE HIGH-TEMP CALL. FOR USE WHEN TOTAL, DESIGN SPACE-HEAT LOAD IS GREATER THAN 80% OF SYSTEM OUTPUT.
MZ systens used in high-temp, low-temp system with high-temp being “piggybacked” through the priority function of MPI’s DHW kit.
MZ
This arrangement uses an indirect DHW tank as a buffer.
A 3-way valve*
B low-temp radiant
C Anti-scald mix valve** on outlet of
DHW tank set at 120 F. max.
D DHW out
E cold potable in
F
G
H
I
BS or other indirect tank
high-temp zone pump
zone valve for high-temp zone
monoflow tee ensures flow
cooperation between DHW and hightemp heat
A
D
E
The high-temp zone’s thermostat is two stage. Stage 1 activates zone valve. The valve’s
C
B
end switch brings on the pump, G. The second stage is wired in parallel with the aquastat
in the tank and brings on the MZ’s burner if needed.
F
I
Control for the low-temp zones B can be whatever would otherwise be used, including outdoor
reset. Constant circulation recommended.
G
When there is a high-temp zone call the pump will circulate water from the tank’s heat exchanger
through the zone until the call is satisfied. The tank acts as a buffer. As the tank’s temp falls, the
stat’s second stage brings heating system on.
H
This arrangement prevents tank overheating at times when no high-temp zone call is
needed. The indirect tank aquastat should be set at whatever temp would be normal for that
family’s use. 110 to 120 F. is normal. The thermostatic mix valve C MUST always be used
to prevent scalding.
There is no conflict between simultaneous DHW and high-temp zone use because high-temp
zone call is above the mix temp of C. Simultaneous use will lengthen the time the MZ will
run to satisfy, but will not interfere with comfort.
If there is a large hot tub or multiple high-flow shower heads, additional DHW storage or more heating system BTUs would be needed in any case. High-temp design must
be at 170 F. or less. If higher temps required, contact MPI. There is no flow conflict between the high-temp zone and the MZ when both priority (DHW / high-temp) circuits
are calling at the same time. The flows are “coupled” only through the indirect tank’s heat exchanger. Flow rates will change depending on whether one or both are calling,
but each circuit will be free to perform its function without interference.
* included in MPI’s DHW kit, part # 9523 ** MPI part # 9075
Note that this is not a design for a specific job. It is a schematic representation of fluid flow patterns suitable for some combined low / high temperature hydronic systems. It shows
one way of solving one of the design challenges normal to combining low and high temperature requirements in hydroninc heating. This drawing is for reference only. It is not
intended to describe a complete system. Each system should be designed by a professional.
25
www.monitorproducts.com
APPENDIX A
A 3-way valve, part of MPI’s DHW kit, part# 9523. When the aquastat in the DHW storage tank (B) calls for heat, the 3-way valve in the MZ will switch to the DHW position
and the MZ will fire and run until the aquastat is satisfied. When the DHW call is finished the 3-way valve moves to the space-heat position.
B DHW storage tank. (MPI BS tank. 25, 40, 50 or 80 gal.)
C Balancing valve.
D Thermostatic modulating zone valve.
E Master zone containing thermostat.
F Street or well water in.
MZ
G Potable DHW out.
25C
H DHW re-circ pipe in BS tank for optional re-circ loop.
Note that there should be a properly-anticipated standard thermostat in zone M. (Call this the “master”
or “reference” zone. It controls supply-water temperature automatically.) When the summer-winter
switch on the MZ’s control panel is in the winter mode, the 85-watt pump in the MZ will circulate
constantly, feeding either the space-heat zones or the DHW call. When the switch is in the summer
mode, the MZ will only respond to a DHW call.
The thermostat automatically modulates the supply water temperature in the winter mode. The
slave zone will always see system-water flow at the temperature determined by the stat in the
master zone. The slave zone, controlled by D, can be set back cooler than the master zone. To
increase temperature in the slave zone, use a balancing valve to reduce flow to the master zone
gradually.
C
E
B
F
Cap.
Flue gas from MZ
Flue gas out.
All pipe 3" PVC. Connect to
MPI’s accessory #9530 A,
separated vent kit.
Existing chase (for instance,
chimney, after cleaning)used for
flue and intake-air runs.
Continuous 3" PVC run for
intake-air is preferred,
especially if very clean chase
cannot be assured. DO NOT
USE CHLORINATED
CLEANERS FOR CHASE
CLEANING!!!
NOTE: This schematic is a generic example of a concept, not a system design. The person using
this concept in any design must take full responsibility for the function of the system. Each system
will be different. This drawing does not show numerous details required for good practice and local
code compliance. Please contact MPI for more information if necessary.
Fresh air intake
H
Combustion-air to MZ
D
Contact MPI for more information. There are many ways of getting great efficiency and comfort.
MZ VENTING USING
CHASE FOR INLET AIR.
A
G
For maximum efficiency, reduce flow through the MZ as much as possible to the point where the
flow switch in the MZ is no longer satisfied or where comfort in very cold weather is compromised
because the MZ is trying to make heat, but is cycling on its adjustable high-limit control.
Note that reducing flow through the MZ means that the last foot of baseboard in a long run can be
much cooler than the first foot when the burner is on for a long time. If baseboard runs through
several rooms in secession, the baseboard should be sized carefully. The MZ can operate at a 50
deg. F. delta T. between return and supply. That’s great for efficiency, but does mean that baseboard
sizing has to be done right.
C
MZ INSTALLATION & MAINTENANCE
26
27
w g
1 2
w
3
On
Off
Switch
4
n
L
120 V. 60 HZ
r
19
Fan
Relay
o
2 1
3
gw
2 1
3
15
Fan
br
r
gw
b
1
2
0
V
o
br
br
gray
Air
Proving
Switch
12
42
r
r
17
10
r
br
br
g
bl
b
bl
w
g
4
3
2
1
7
o
b
Winter
Summer
gray
11
gray
gray
o
13
DHW
Relay
2
4
V
o
o
br
Lead Gas
Valve
20
gray
25
r
Transformer
r
41
Pump
Relay
gray
r
8
T1
b
o
14
Pump
n L
r
o
b
T2
1
2
3
gray
b
o
5
1
2
3
w
o
b
6
3
27
b
2 1
5 4 br
4 5 6
b 27
1 2 3
o
Water Flow
Switch
16
gray
18
1 2
4 r
3
b
2
1
1 2
w
Wire color-code: mote arrows signify return to ground green and neutral (white).
b = black
bl = blue
br = brown
g = green
gr = gray
L = line
n = nueteral
o = orange
r = red
w = white
o
T3
MZ 25C - 25S Wiring Diagram
Valve
Valve (GND)
24 V.
9A
24 V. Ground
Ground
(Burner)
Senior
9B
6
Sequence of Operation: Priority (DHW) Call
On-off switch on. Switch 6 closes on fall, brining 24v to relay 13 which calls for
pump through relay 41 and initiates ignition sequence, bypassing stage one of
aquastat 8. Call for heat is thus available through wiring harness 27 whether of
not unit is in between 10 and 11 to protect manual-reset supply-water limit 11
from nuisance trip.
Sequence of Operation: Space-Heat Call
On-off switch 4: on. Summer-winter switch 5 (SWS): winter. 24v @ T1 through
SWS. 24v @ T2 brings on pump 14. 24 @ T3 goes through adjustable supplywater aquastat 8, water limit 11, to flue limit 10 air-proving switch is closed, 24v
closes fan relay 19. At air-proving switch 12 close, 24v at ignition module 20
initiates combustion by powering gas valve 17 while powering spark through
ignition transformer 18. At four-seconds into ignition sequence, flame-proving
is checked through proving rod 25. If flame is proved, heating system then supplies
heat until call for heat or DHW is satisfied. If leaving-water temperature exceeds
setting on aquastat 8 burner will shut off until supply-water temperature falls
below its setting until the call for heat has been satisfied.
Component Key [MPI Part Numbers]
1) Line (120 V.)
2) Ground
3) Neutral (common)
4) On-off switch
5) Summer (S) winter (W) switch
6) Field-supplied external close-on-fall switch for DHW or other priority call
7) Three-way value [Part of DHW kit 9523
8) Adjustable aquestat for system-water temperature control
9a) Thermostat location for control of pump and burner simultaneously.
9b) Thermostat location for control of burner. Pump runs continuously
10) Manual-reset flue-gas limit [9051]
11) Manual-reset supply-water limits [9023]
12) Air proving switch [9073]
13) DHW relay [9001]
14) Water pump [9006]
15) Combustion-air fan [9019]
16) Water-flow proving switch [9039]
17) Gas valve [9005]
18) Ignition transformer [9020]
19) Fan relay [9001]
20) Ignition module [9016]
25) Flame-proving rod [9003]
27) Wiring harness for priority control [Part of DHW kit: 9523]
41) Water-pump relay [9001]
42) 120/24 V. Transformer [9043]
Note: In the MZ 25S the wiring harness 27 and the aquastat 6 are installed in
the MZ factory. For an MZ25C using MPI’s DHW kit, part #9523, the additional
aquastat that ships with the wiring harness 27 and 3-way valve 7 must be field
installed inside the MZ and wired in series between 10 and 11.
APPENDIX A
www.monitorproducts.com
APPENDIX A
WIRING DIAGRAM FOR FULL OUTPUT CONTROL OF MZ2040C FOR PRIORITY CALL WHEN ADJUSTABLE-LIMIT
SWITCH IS AT LOW-TEMP SETTING.
27
9A
T3
T2
o
RELAY
6
b
3
2 1
6
5 4 br
r
T1
25
VALVE
VALVE (GND)
24 V.
o
br
b
br
20
bl 4
b 3
bl
2
w
1
24 V. GROUND
GROUND
(BURNER)
SENIOR
9B
gray
b
gray
r
4
3
2
1
b
1 2
w
g
gray
b
1 2
w
br
1
FAN
15
br
r
3 2 1
12
14
AIR
PROVING
SWITCH
PUMP
n L
3 2 1
g w
19
FAN
RELAY
41
PUMP
RELAY
gray
o
r
4
ON
OFF
SWITCH
w g
1 2 3
n
L
120 V. 60 HZ
r
r
17
30
LEAD GAS
VALVE
LAG GAS
VALVE
b
1
2
0
V
gray
b
r
br
br
1
2
3
11
10
r
13
DHW
RELAY
o
br
br
gray
gray
o
16
WATER FLOW
SWITCH
44
LAG
VALVE
RELAY
w
b
o
b
b
Summer
2
4
V
42
br
1
2
3
gray
TRANSFORMER
r
18
g
r
o
gw b
w
b
8
o
o
o
2
o
Winter
br
1 2 3
o
gray
5
4 5 6
b 27
br
Wire color-code: mote arrows signify return to ground green and neutral (white).
b = black
bl = blue
br = brown
g = green
gr = gray
L = line
n = nueteral
o = orange
r = red
w = white
Note that the additional relay to bring full output to a priority call is field installed. Note that the grey and black wires used to
power the additional relay are also used to power the 3-way valve when MPI’s 3-way valve kit, part # 9523, is used for
prioritizing. If prioritizing is done through a pump-control switching box, use MPI part # 9518, wiring harness, item #27 in this
drawing, to connect the MZ to the additional relay and priority-controller end switch.
Note that the relay shown is available from MPI as our part # 9001. The use of the transformer in the MZ to power other
relays or other controls is not recommended.
MZ INSTALLATION & MAINTENANCE
28
APPENDIX B
V I
I .
A P P E N D I X
PARTS:
The MZ is an exceptionally well-built device. All of the
components selected for the MZ are the most reliable
available. No matter how well built and reliable a product is,
parts are inevitably needed. We are committed to making
parts readily available for the MZ through your distributor,
even though they should seldom be needed.
B
CONTROL PANEL MZ25C/S
REQUIRED PARTS LIST
PART# 9016 IGNITION MODULE
PART# 9020 IGNITION TRANSFORMER
PART# 9043 TRANSFORMER
PART# 9019 FAN
PART# 9015 FLOW SWITCH FOR 25 SERIES
PART# 9039 FLOW SWITCH FOR 40 SERIES
PART# 9007 ADJUSTABLE LIMIT SWITCH
PART# 9011 RELIEF VALVE
PART# 9005 GAS VALVE
The following parts are specific to the MZ25S:
PART# 9008 DHW AQUASTAT
PART# 9018 THREE-WAY VALVE OPERATOR
Full stock of the remainder of the parts
for the MZ line is available from the source
of your MZ.
ITEM
ITEM
PART
#
1
2
NUMBER
Reference Only
9055
3
4
Reference Only
9051F
5
6
9053
9007
7
8
Reference Only
Reference Only
9 Reference Only
10 Reference Only
FRONT COVER & STICKER
ON/OFF SWITCH
#
11
12
PART
NUMBER
9001
Reference Only
DESCRIPTION
RELAY, 24V COIL
RELAY CARRIER & STIRRUP
SUMMER/WINTER SWITCH
THERMOSTAT GAUGE FAHRENHEIT)
13
14
Reference Only
Reference Only
FOLDED RELAY HOLDER
WHITE CONTROL BOX
KNOB
SYSTEM THERMOSTAT 20-80º C
15
16
ZINC DISC D 4XX10X0,8
WIRE ROPE CLAMP
17
*
FOLDED NECK FOR WIRES
COVER FOR CONTROL BOX
*
DESCRIPTION
9061
9043
9070
Reference Only
9017
CLIP
TRANSFORMER 120 TO 24 VOLTS
CONTROL BOX
SAFETY BOX WIRED
CONTROL PANEL INCLUDING WIRING
*NOT SHOWN ON DRAWING
29
www.monitorproducts.com
APPENDIX B
MZ25C
MZ INSTALLATION & MAINTENANCE
30
APPENDIX B
ITEM
PART
#
NUMBER
ITEM
PART
#
NUMBER
1
2
9065
9056
DRAIN VALVE WITH CAP
STRAINER
32
33
9533
9003
ELBOW D.80 45º
FLAME PROBE
3
4
9078
9056
RETURN-WATER MANIFOLD GASKET
NEOPRENE STICKING SEALING
34
35
9022
9004
BURNER HEAD
IGNITOR
5
9093
FLANGE
RETURN/SUPPLY MANIFOLD, MZC
36 For Reference Only AIR REDUCER D.29 (GN)
36 Part of LP Kit 9085 AIR REDUCTION RING D.31 (GP)
6
9042
O RING FOR DERATE ORIFICE
HEAT EXCHANGER
37 For Reference Only REMOVABLE PROTECTION FOR
BURNER (580 X 30 X 1.5)
7
8
9006
9096
CIRCULATING PUMP 15/42F 115V
NEEDLE VALVE O-RING
38 For Reference Only GLASS BRAID RING D 12 LG 685
39
9023
SYSTEM LIMIT
9
10
9095
9094
BYPASS NEEDLE VALVE
BYPASS PLUG
40
41
9532
9024
90º ELBOW D 80 WITH SENSOR
FLUE LIMIT 76º C
11
12
9010
9015
AUTOMATIC AIR VENT
FLOW SWITCH
42
43
9060
9059
SIGHT GLASS RETAINER
SIGHT GLASS GASKET
13 For Reference Only SPRING FOR SYSTEM COVER
14 Part of LP Kit 9085 UNION REDUCER D 3.5 (GP)
44
45
9058
9014
SIGHT GLASS
SYSTEM HEAT EXCHANGER
14
9130
UNION REDUCER 5.4 (GN)
15 For Reference Only SAFETY VALVE DISCHARGE PIPE
47
48
9069
2365
PRESSURE RELIEF VALVE
FLEXIBLE PIPE/SIPHON OUTLET
16
16
49
9017
D.32 LENGTH 1300
CONTROL PANEL INCLUDING WIRING
9098
9090
DESCRIPTION
RETURN TO HX PIPE
WELDED INLET TO SUMP
DESCRIPTION
17 For Reference Only EXTENSIBLE SEALING EXT. 40
INTERNAL 25
50
9066
NUT
51 For Reference Only FLANGE COCK & EXPANSION
18
19
VESSEL FOR THR
52 For Reference Only STAINLESS STEEL FLEXIBLE PIPE
9019
9099
FAN (OR #W00. 17073)
RETURN TO HX PIPE GASKET
20 For Reference Only SLEEVE BURNER/VALVE 2 PARTS
TO CLIP
MALE, 1/4 WITH ELBOW
53 For Reference Only SIGHT GLASS D 33X3
21 For Reference Only NITRILE O-RING D 38 3.70 SHORE
22 For Reference Only COLORLESS PLASTIC CAP
54
9080
GAS MANIFOLD CONNECTION NUT 25S
55 For Reference Only SEALING
23
24
9097
9534
FLOW SWITCH GASKET
WALL BRACKET
56
57
9012
EXPANSION VESSEL (8 LITERS)
For Reference Only GAS SUPPLY
25
26
9210
9020
CABINET MZ25C
IGNITION TRANSFORMER
58
59
9005
GAS VALVE
For Reference Only NITRILE O-RING D.23 52X1, 78
27 For Reference Only BACK STOP PLATE FOR MZ
(3355X80 4X1.5)
60
61
For Reference Only BURNER GAS PIPE
For Reference Only WHITE DOOR FOR MZC 525 NOT
28 For Reference Only FIXING SYSTEM FOR FLUE PIPE
29 For Reference Only EXTENSIBLE SEALING;
52
EQUIPPED
For Reference Only WHITE ABS DOOR HANDLE 90, 22,
63
90,79, O B
DOOR MZ25C
EXT40-INTERN, 14
30 For Reference Only REDUCED FLUE OUTLET PIPE,
31
9021
F75/M80 L360
AIR PRESSURE SWITCH
64
65
31
9206
9207
WHITE COVER MZC: WHITE DOOR
For Reference Only NITRILE O-RING D.8X2 80 SHORE
www.monitorproducts.com
APPENDIX B
MZ25S
MZ INSTALLATION & MAINTENANCE
32
APPENDIX B
ITEM
PART
#
NUMBER
ITEM
PART
#
NUMBER
DESCRIPTION
DESCRIPTION
1
For Reference Only SPRING FOR SYSTEM COVER
38
For Reference Only NITRILE O-RING
2
For Reference Only EXTENSIBLE SEALING;
EXT40-INTERN 14
39
40
9019
FAN (OR #W00. 17073)
For Reference Only EXTENSIBLE SEALING EXT. .40
41
INTERN 25
For Reference Only GALVANIZED CAST IRON BEND
42
43
9009
3 WAY SELECTOR VALVE SHELL
For Reference Only HEATING FLOW MZS
44
45
9015
FLOW SWITCH
For Reference Only WELDED INLET TO PUMP
2
3
9065
BOTTOM PANEL, MZ25S 40
FILL/DRAIN VALVE WITH CAP
4
5
9056
9068
STRAINER
WASHER
6
7
For Reference Only HEATING FLOW/RETURN UNIT
For Reference Only NEOPRENE STICKING SEALING/
8
9096
FLANGE
NEEDLE VALVE O-RING
46
48
9094
9018
BYPASS PLUG
SELECTOR VALVE MOTOR
9
10
9095
9094
BYPASS NEEDLE VALVE
BYPASS PLUG
49
2365
FLEXIBLE PIPE/SIPHON OUTLET
D32 LENGTH 1300
11
12
9010
AUTOMATIC AIR VENT
For Reference Only SEAL, AFM34 D
50
51
9057
CONDENSATE TRAP
For Reference Only GLASS BRAID RING D12 LG 685
13
14
9069
9006
SAFETY VALVE MF 1/2"
CIRCULATING PUMP 15/42F 115V
52
53
9023
9014
SYSTEM LIMIT
HEAT EXCHANGER MZ25C / MZ25S
15
16
9099
9082
RETURN TO HX PIPE GASKET
DHW LEAVING-WATER ELBOW 25S
54
9024
ELMWOOD SAFETY THERMOSTAT
85º W/ MANUAL RESET
55
56
9532
9060
90º ELBOW D80 WITH SENSOR
SIGHT GLASS RETAINER
57
58
9059
9058
SIGHT GLASS GASKET
SIGHT GLASS
17
18
19
20
21
9081
DWH FLOW-SET ELBOW 255
For Reference Only MESSING MF REDUCTION
9080
9013
GAS MANIFOLD RETAINER NUT
FLASH DOMESTIC HOT WATER
CYLINDER
For Reference Only BRASS NIPPLE MALE 1/2 -
59
60
9017
CONTROL BOX
For Reference Only UNION REDUCER D 3.5
For Reference Only UNION REDUCER 5.4
For Reference Only NIRILE O-RING D 8X2 80 SHORE
22
9535
MALE 3/4 LONG
WALL BRACKET
60
61
23
24
9212
9008
CABINET MZ 25S
DOMESTIC HOT WATER
62 For Reference Only BURNER GAS PIPE
63 For Reference Only NIRILE O-RING D 23.52 X 1.78
25
9020
THERMOSTAT
IGNITION TRANSFORMER
64
65
9005
GAS VALVE
For Reference Only GAS SUPPLY
66
67
9012
EXPANSION VESSEL (8 LITERS)
For Reference Only STAINLESS STEEL FLEXIBLE PIPE
26
27
For Reference Only BACK STOP LATE FOR MZ
For Reference Only FIXING SYSTEM FOR FLUE PIPE
28
29
9533
9097
ELBOW D.80 45º
FLOW SWITCH GASKET
68
MAL 1/4 WITH ELBOW
For Reference Only SIGHT GLASS D 33X3
31
32
9021
9003
AIR PRESSURE SWITCH
FLAME PROBE
69
70
9066
NUT
For Reference Only FLANGE COCK & EXPANSION
33
34
9004
9022
IGNITOR
BURNER HEAD
71
VESSEL FOR THR
For Reference Only COVER MZS: WHITE
35
9092
RETURN/SUPPLY HEAT EXCHANGE
O-RING
72
For Reference Only WHITE DOOR MZS/THRS NOT
EQUIPPED
For Reference Only WHITE ABS DOOR HANDLE 50, 22,
90, 79, 0B
36
36
For Reference Only AIR REDUCER D29
9129
AIR REDUCTION RING D.31
73
37
Part of LP Kit 9084 SLEEVE BURNER/VALVE 2 PARTS
TO CLIP
74
33
9200
DOOR MZ40
www.monitorproducts.com
APPENDIX B
MZ25S
MZ INSTALLATION & MAINTENANCE
34
APPENDIX B
ITEM
PART
#
NUMBER
1
2
3
4
For Reference Only
For Reference Only
9005
For Reference Only
DESCRIPTION
ITEM
PART
#
NUMBER
DESCRIPTION
BURNER GAS PIPE
FIXING BRACKET FOR IONIZATION
20
21
For Reference Only CIRCULATING PUMP 15/42F 115V
For Reference Only FIXING BRACKET/TURBINE
PROBE
GAS VALVE
22
23
For Reference Only VERSILIC 6X10 LG 300 MM
For Reference Only JOINT BRIDGE CIRCULATOR UPS
FIXING BRACKET FOR BURNER
MZTHR
24
15-42 F D.55 EP.5
For Reference Only FIXING U-PART FOR THE TURBINE
5
6
9024
9058
FLUE LIMIT 76º C.
CONDENSATE TRAP
25
26
7
8
9059
9060
SIGHT GLASS
SIGHT GLASS RETAINER
27
For Reference Only SLEEVE BURN/VALVE 2
PARTS TO CLIP
28
29
For Reference Only JOINT TORQUE NITRILE
For Reference Only SYSTEM SHELL
9
10
11
12
For Reference Only GAS SUPPLY
For Reference Only NON-RETURN VALVE
9011
9012
SAFETY VALVE MF 1/2"
EXPANSION TANK
30
31
13
For Reference Only FLEXIBLE PIPE/SIPHON
OUTLET D 32 LENGTH 1300
32
33
14
15
9057
STRAINER
For Reference Only DRAIN VALVE WITH
34
35
9084
9019
9098
9099
LP CONVERSION KIT MZ40
FAN (OR #W00. 17073)
RETURN TO HX PIPE
RETURN TO HX PIPE GASKET
For Reference Only GLASS BRAID RING D 12 LG 685
9023
SYSTEM LIMIT
9022
9004
BURNER HEAD
IGNITOR
9025
CAP M 1/2 - M 3/4
CONNECTING TUBE
36
16
For Reference Only ADAPTER D. 4-D 6.35
REF: CABGEM02 (MZ USA)
17
9068/9078
(EXPANSION TANK)
WASHER
37
38
9003
FLAME PROBE
For Reference Only HEATING FLOW BEND
18
19
9056
STRAINER
For Reference Only HEATING FLOW/RETURN UNIT
35
www.monitorproducts.com
APPENDIX B
MZ40C
MZ INSTALLATION & MAINTENANCE
36
APPENDIX B
ITEM
#
PART
NUMBER
DESCRIPTION
1
9091
FILTER FILL AND DRAIN A55Y
42
DRAIN VALVE WITH CAP M1/2-,3/4"
MESSING REDUCER CB 1 1/2 -
43
44
For Reference Only
For Reference Only
TINNED GAS PIPE NOZ
MESSING M/F REDUCTION
2
3
9065
For Reference Only
ITEM
#
PART
NUMBER
DESCRIPTION
9093
RETURNS/SUPPLY MANIFOLD, MZC
4
9066
FEMALE 1/2
NUT
45
46
For Reference Only
For Reference Only
90 ELBOW D. 80 WITH SENSOR
GLASS BRAID RIND D. 12 LG 1070
5
6
9056
9078
STRAINER
RETURN WATER MANIFOLD
47
For Reference Only
ELMWOOD SAFETY THERMOSTAT
85º W/ MR
GASKET
NEOPRENE STICKING SEALING/
48
49
9005
For Reference Only
GAS VALVE
NITRILE O-RING D. 23, 52X 1.78
50
51
For Reference Only
9097
HONEYWELL VALVE FLANGE
FLOW SWITCH GASKET
For Reference Only
9060
SIGHT GLASS D. 33X3
SIGHT GLASS RETAINER
7
For Reference Only
8
9096
FLANGE
NEEDLE VALVE O-RING
9
10
9095
9094
BYPASS NEEDLE VALVE
BYPASS PLUG
52
53
11
12
9010
9015
AUTOMATIC AIR VENT
FLOW SWITCH
54
55
9059
9058
SIGHT GLASS GASKET
SIGHT GLASS
INLET/OUTLET HEATING UNIT
RETURN/SUPPLY HEAT
56
57
9087
9080
MZ40C HEAT EXCHANGE
DWH CONNECTION NUT 255
EXCHANGE O-RING
CIRCULATING PUMP 15/42F 115V
58
59
13
14
15
For Reference Only
9092
9006
For Reference Only
9057
16
17
For Reference Only
9090
SPRING FOR SYSTEM COVER
SAFETY VALVE DISCHARGE PIPE
60
18
19
9098
For Reference Only
RETURN TO HX PIPE
WHITE DOOR MSZ/THRS NOT
EQUIPPED
61
62
9011
For Reference Only
SAFETY VALVE MF 1/2"
FLEXIBLE PIPE/SIPHON OUTLET
D. 32 LENGTH 1300
RETURN TO HX PIPE GASKET
FAN (OR #W00 17073)
63
*
For Reference Only
For Reference Only
COVER MZC 30/40 WHITE
WIRE CARRIER
*
*
9002
For Reference Only
O-RING (FLUE OUTLET)
EPOM STICKING SEAL PIPE 6/9
For Reference Only
LENGTH 18
EXTENSIBLE SEALING, EXT. 40-
20
21
22
23
24
9099
9019
For Reference Only
For Reference Only
COLORLESS PLASTIC CAP
WHITE ABS DOOR HANDLE 90, 72,
For Reference Only
90, 79, OB
EXTENSIBLE SEALING EXT. 40
*
*
9104
GAS RAMP M40
CONDENSATE TRAP
CONTROL PANEL INCLUDED
WIRING
25
9535
INTERN 25
WALL BRACKET
26
27
9205
9020
CABINET, MZ40
IGNITION TRANSFORMER
*
For Reference Only
FLUE PIPE
FLUE TEMPERATURE ALU
*
For Reference Only
MEASURE SENSOR
FIXING BRACKET FOR BURNER
9101
INTERN 14
GASKET FOR 70 MM HORIZONTAL
28
29
For Reference Only
For Reference Only
BACK STOP PLATE FOR MZ
FIXING SYSTEM FOR FLUE PIPE
30
31
9200
For Reference Only
DOOR MZ40
REDUCED FLUE OUTLET PIPE
*
For Reference Only
MZ/THR
VERSILIC PIPE 6X10 LENGTH 800 MM
32
33
9073
For Reference Only
AIR PRESSURE SWITCH 40C
ELBOW D. 80 45º
*
*
For Reference Only
For Reference Only
GAS BEND
HEATING FLOW BEND
FLAME PROBE
IGNITOR
*
*
For Reference Only
9087
HEATING RETURN BEND
LP CONVERSION KIT MZ40
*
34
35
9003
9004
36
37
9023
For Reference Only
SYSTEM LIMIT
NITRILE O-RING D.38X3.70 SHORE
9077
COMBINATION RESET SWITCH
ASSEMBLY
38
39
For Reference Only
For Reference Only
NITRILE O-RING D 8X2 80 SHORE
UNION REDUCER D12 D 4.20 (GP)
*
For Reference Only
FIXING BRACKET FOR
IONIZATION PROBE
40
41
9074
For Reference Only
BURNER FOR MZ40C
SLEEVE BURNER/VALVE 2 PARTS
*
*
For Reference Only
IGNITION ANGLE WITH SCREW
*NOT SHOWN ON DRAWING
TO CLIP
37
www.monitorproducts.com
APPENDIX B
ITEM
#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
*
*
PART
NUMBER
For Reference Only
9055
9054
9051F
9053
9052
For Reference Only
For Reference Only
For Reference Only
For Reference Only
9001
For Reference Only
9040
For Reference Only
For Reference Only
9061
9043
9016
For Reference Only
9104
DESCRIPTION
FRONT COVER & STICKER
ON/OFF SWITCH
SUMMER/WINTER SWITCH
THERMOSTAT GAUGE (FAHRENHEIT)
KNOB
ADJUSTABLE LIMIT 40
ZINC DISC D 4XX10X0.8
WIRE ROPE CLAMP
FOLDED NECK FOR WIRES
COVER FOR CONTROL BOX
RELAY MY4-24V
RELAY CARRIER & STIRRUP
120V RELAY
FOLDED HOLDER/RELAY
WHITE CONTROL BOX
CLIP
TRANSFORMER 120 TO 24VOLTS
CONTROL BOX
WIRING
CONTROL PANEL INCLUDED WIRING
ITEM
BS 25/40/50/80
MZ INSTALLATION & MAINTENANCE
#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
18
18
18
*
*
MZ40C
PART
NUMBER
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
9400
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
For Reference Only
9401
For Reference Only
For Reference Only
38
DESCRIPTION
Grey Ps Cleaning Door
Anode & Cap & Sealing 3/4d.22.230 magnesium
Flange for cleaning door
Sealing AFM34 D.36x26x2
Sealing/Cleaning Door
Anode Cleaning Door
Upper Bottom & Cable BS
Jaeger Tuaa5C112 Jaeger Thermostat
Black Cap for the Thermostat
Black Thermostat Knob
Thermostat Rect Horiz 69x14 LG Capil 1500 MM
Thermoformed
Stainless Steel Bend 90 Degree M3/4-F3/4
Domestic Cold Water Pipe Length 310
Plug Wieland 5 PT. Male
Plug Wieland 5 PT. Female
Fixing Piece
ABS Sheet; Ep:08 1935x440 BS100
ABS Sheet: EP: 081935x665 BS150
ABS Sheet; EP: 08 1935x890 BS200
ABS Sheet; EP: 081935x1340 BS300
NBS Superior Bottom Equipped
Wiring
NOTES
MONITOR PRODUCTS, INC.
P.O. Box 3408 • Princeton, NJ 08543
www.monitorproducts.com
PHONE (732) 329-0900 • FAX (732) 329-0904
MPI offers technical support to qualified licensed heating contractors during normal business hours. (Monday-Friday 8:30
A.M. to 4:30 P.M. Eastern Time) To help us serve you properly our technicians will require the following information:
Fuel Type (Natural/Propane)
Gas pressure in In. W.C. (Inlet and outlet with all appliances running)
CO reading in PPM O 2 reading in %
Flue Outlet Temperature °F
Water Outlet temperature °F Water Return temperature °F
System load: Radiant, high temperature, DHW. Total BTU requirement
Input Voltage
39
www.monitorproducts.com
WARRANTIES
VIII - M O N I T O R P R O D U C T S , I N C . ( “ M P I ” ) L I M I T E D WA R R A N T I E S
First year-MPI warrants that each MZ Series Heating Systems
sold by it to be free from defects in material and workmanship,
under normal use and services, for a period of 1 year after date
of purchase with an additional period of up to 3 months if unit
is not installed at the time of purchase.
First through tenth year-MPI warrants that the primary heat
exchanger assembly consisting of water-tube heat exchanger,
water jacket and condensate collector is free from defects in
material and workmanship for 10 years from the date of
purchase.
MPI corrosion inhibitor must be used in every MZ series heating
system. Failure to use this inhibitor will void this warranty.
NOTE: We will not accept any MZ heat exchangers
for warranty consideration without an 8 ounce water
sample from the system. This is required to test for
the proper inhibitors. No credit will be issued
without a water sample.
STANDARD PROVISIONS, TERMS AND CONDITIONS THAT
ARE COMMON TO ALL MPI INDIVIDUAL PRODUCT
WARRANTIES:
These warranties are subject to the condition that the MPI
product(s) must have been installed in accordance with
manufacturer’s instructions. These warranties extend only to
the first retail purchaser of the products and only to a product
that has not been moved from its original installation site. These
warranties do not apply to commercial applications.
In addition to each product warranty listed, MPI warranties
do not cover:
1) Components that are part of the heating system but
were not furnished by MPI as part of the heating system.
2) The workmanship of any installer of MPI’s product(s).
In addition, this warranty does not assume any liability
of any nature for unsatisfactory performance caused by
improper installation.
3) Any costs for labor for removal and reinstallation of the
alleged defective part, the cost of shipping or
transportation to MPI and back to the consumer, if
necessary, and any other materials necessary to perform
the exchange.
4) Replacement parts beyond the balance of the original
warranty period.
REMEDY: If within the applicable warranty period, any product(s) or part(s) included in this warranty proves to be defective
in material and/or workmanship, then MPI shall repair or
replace, at its option, the defective product(s) or part(s) and
return it to the consumer.
MZ INSTALLATION & MAINTENANCE
PROCEDURE FOR OBTAINING PERFORMANCE UNDER
THIS WARRANTY: In order to obtain performance under this
warranty, the original purchaser must promptly (in no event
later than thirty (30) days after discovery of the defect) see to
the return of the product(s) or part(s) in question, accompanied
by a properly filled out MPI warranty claim form (Available
from MPI by mail or phone). Any claim made under this warranty
must be accompanied by proof of original purchase date, sales
invoice or cancelled check showing the serial number as
satisfactory evidence. Any replacements are made subject to
validation by MPI of in-warranty coverage. An item to be
replaced must be made available in exchange for the
replacement.
SOLE REMEDY: The remedy and liability for any breach of
warranty, express or implied, set forth herein is the sole and
exclusive remedy and the limit of liability for any such breach.
EXCLUSIONS AND IMPLIED WARRANTIES: This warranty
does not extend to any defect due to the negligence of others.
Failure to install, operate or maintain the product(s) in
accordance with the installation, operation and maintenance
instructions furnished with each new product, unreasonable
use, accidents, acts of god, fire, snow, floods, lightning,
alteration, ordinary wear and tear, or the use of unauthorized
or non-standard parts.
ALL IMPLIED WARRANTIES, IF ANY, ARISING UNDER LAW
IN CONNECTION WITH THE SALES BY MPI OF ANY
PRODUCT(S) ARE LIMITED IN EXTENT AND DURATION
TO THE DURATION OF THIS WRITTEN WARRANTY. THERE
ARE NO WARRANTIES, EXPRESS OR IMPLIED, OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE OTHER THAN AS EXPRESSLY STATED HEREIN.
MPI SHALL NOT BE RESPONSIBLE FOR ANY INCIDENTAL,
INDIRECT, PUNITIVE, OR CONSEQUENTIAL DAMAGES
WHETHER AS A RESULT OF BREACH OF WARRANTY,
NEGLIGENCE, STRICT LIABILITY IN TORT OR
OTHERWISE.
Note: Some jurisdictions do not allow: (a) limitations on how
long an implied warranty lasts; or (b) the exclusion or limitation
of incidental, indirect, punitive or consequential damages, so
the above limitations or exclusions may not apply to you.
NO VARIATION OF TERMS: the parties intend that this
warranty be the exclusive and final expression of their
agreement.
No person has the authority to orally, in writing or in any other
way vary the terms, conditions or exclusions of this warranty,
or to make any express warranties other than those contained
herein.
LEGAL RIGHTS: This warranty gives you specific legal rights
and you may also have other rights which vary from jurisdiction
to jurisdiction.
40