Installation, Operation, and Maintenance Contents

Installation, Operation,
and Maintenance
940126-0001 Rev L
Heat Pump Water Heaters
1. INTRODUCTION ..................................................................................................... 1
2. GENERAL ............................................................................................................... 1
3. WATER QUALITY ................................................................................................... 2
4. EQUIPMENT SIZING .............................................................................................. 5
5. STORAGE TANK SIZING ........................................................................................ 5
6. INSTALLATION ....................................................................................................... 6
7. OPERATION.......................................................................................................... 11
8. MAINTENANCE..................................................................................................... 21
COLMAC WaterHeat
1.1. Heat Pump Concept
1.1.1. Colmac air and water source heat pumps offer the commercial hot water user a
highly energy efficient means of generating potable hot water. The Colmac heat
pump water heater uses the same operating principle as an air-conditioner or
domestic refrigerator. The heat pump gathers heat from a suitable fluid, and
through the refrigeration cycle, deposits the heat into water at a useable
temperature. This principle of moving heat with a heat pump, rather than
generating it by burning fossil fuel (i.e. natural gas), or electric resistance, makes
water heating with heat pumps the best choice for conserving fossil fuels.
Depending on the temperature of the heat source supplied to the heat pump, water
can be heated using one third to one fifth of the energy required by electric
resistance, or gas.
1.1.2. Since the Colmac heat pump uses the same principle as an air-conditioner, it
produces cool air or water as it makes hot water. This "free" cooling benefit can be
put to use to supplement the existing air-conditioning system, or to provide "spot
cooling" to hot work areas.
1.1.3. The maximum leaving water temperature that can be produced by any heat
pump water heater is determined by the maximum allowable pressure of the
refrigerant. The Colmac heat pump uses environmentally friendly R-134a
refrigerant which operates at lower pressures than R22. This allows the heat pump
to produce maximum leaving water temperatures up to 160°F (71°C).
1.1.4. Remember that average tank temperature sensed by the aquastat bulb will be
somewhat lower than the water temperature leaving the heat pump. This means
the practical maximum aquastat set point will be between 140° and 150°F (60° and
2.1. Air Source Heat Pump (HPA) Applications
2.1.1. Colmac Air Source Heat Pump (HPA) heat pumps can be successfully applied
wherever there is a need for large amounts of hot water and there is a source of
warm air available. The Colmac HPA is best suited for supplying hot water in
commercial facilities where demands for hot water and space cooling are
concurrent, or where there is a demand for hot water and ambient air temperatures
do not fall below 50°F (10°C).
2.1.2. There are two basic types of applications for Colmac HPA heat pumps:
Water Heating Only. In these applications, hot water is made energy efficiently while
the air-conditioning benefit is not used because of building configuration and other
reasons. These systems are the simplest to design and control; however, since the
air-conditioning effect is not used it cannot be taken as added savings in the
economic payback analysis. Examples of this type of building would be Apartments,
Condominiums, Hotels, Hospitals, or Dormitories located in warm climates.
Water Heating with Air-Conditioning (A/C) Benefit. Here the cool air produced by the
Colmac HPA is used to cool an occupied space while energy efficient hot water is
being made. When the A/C benefit is used it becomes important to know and/or
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calculate both the hot water and air-conditioning loads and the profiles of both loads
throughout the day. There are two possible cases when using the A/C benefit:
The Hot Water Load exceeds the A/C Load. In this case, size the HPA for the A/C
load and deposit the hot water in a preheat tank to feed the main water heating
system. Use a room thermostat in series with the preheat tank aquastat to control the
HPA to prevent "overcooling" of the space where the HPA is located.
The A/C Load exceeds the Hot Water Load. Here, again, there are two strategies for
sizing the HPA. The designer can 1.) Size the HPA to match the Hot Water Load and
"assist" the A/C system by ducting the cool air for "spot cooling", or 2.) Size the HPA
to match the A/C load and incorporate a "Remote Heat Rejection" option.
Examples of applications requiring concurrent space cooling and water heating are:
Restaurants, Nursing Homes, Laundries, Hospitals, Kitchens, Food Processing
Plants, Photographic Processing Plants, etc.
2.1.3. Limitations
The Colmac HPA heat pump capacity is affected by the temperature of the entering air.
As entering air temperature falls, so does heat pump capacity and efficiency. The
minimum allowable entering air temperature is 50°F (10°C). For conditions outside of
these parameters, consult the factory.
2.2. Water Source Heat Pump (HPW) Applications
2.2.1. Colmac Water Source Heat Pumps (HPW) use waste heat in the form of any
filtered, non-corrosive, pressurized stream of liquid at temperatures as low as 50°F
2.2.2. Building hydronic loop water, return chilled water, condenser or cooling tower
water, geothermal loops or wells, and industrial process water are a few of the
possible heat sources that can be utilized by the HPW heat pump.
2.2.3. Limitations
The Colmac HPW heat pump capacity is affected by the temperature of the source
water. As source water temperature falls, so does heat pump capacity and efficiency.
The minimum allowable source water temperature is 50-55°F (10°- 13°C). For
conditions outside of these parameters, consult the factory.
3.1. Colmac Heat Pump Water Heaters use stainless steel, copper brazed, plate heat exchangers
(condensers) to transfer heat from the condensing R-134a refrigerant to water. Standard heat
pump units are supplied with copper water piping and condensers which may be affected by poor
quality water. Following are guidelines for determining the acceptability of standard copper
construction in terms of water quality.
3.2. One very general method of describing water quality is Total Dissolved Solids, TDS, in Parts Per
Million, ppm. In broad terms:
100 ppm or less TDS = good quality drinking water
500 ppm TDS = marginally drinkable water
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COLMAC WaterHeat
1200 ppm TDS = considered "brackish" water
3.3. Standard HPA/HPW units with copper condensers should operate acceptably with water having
up to 500 ppm TDS provided there are no sulfides (i.e. Hydrogen Sulfide) present.
3.4. If sulfides are present and/or TDS is 500 ppm or higher, then Nickel brazed condensers must be
used. The Colmac factory must be consulted regarding pricing for these special units.
3.5. Cleaning of the condensers should not be necessary under most conditions (even with marginal
quality water) for the following reasons:
3.5.1. Turbulence of the water flowing through the condenser tubing will keep solids in
3.5.2. Surface temperatures in the condenser are normally below the level at which
calcification will occur.
3.5.3. This has been confirmed by field experience in Hawaii and elsewhere.
3.6. If condensers must be cleaned, an organic acid (vinegar) solution flushing procedure can be
performed (see Section 8.24 on De-liming).
3.7. If there are further concerns and questions about specific cases of poor quality water, then the
following information should be obtained and relayed to Colmac:
What is the pH?
What is the Calcium level?
What is the Alkalinity?
Are Chlorides present? If so, in what amounts?
Are Sulfides present? If so, in what amounts?
These values should be within the limits of the following:
Table 1 - Influence of Chloride on Corrosion Resistance at Varying Temperatures
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Table 2 - Influence of Water Composition on Corrosion Resistance
Good resistance under normal conditions
Corrosion problems may occur especially when more factors are valued 0
Use is not recommended
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3.8. Colmac water source heat pump water heaters (HPW) use stainless steel, copper brazed, plate
heat exchangers (evaporators) to transfer heat from the source water to the evaporating R-134a
refrigerant. Mechanical filtration is an important consideration on the source water side of the
water source heat pump. If the potable or source water contains particles larger than 0.04
inches (1 mm), Colmac recommends a strainer with a size of 16-20 mesh (number of
openings per inch) is installed before the source water evaporator. Failure to meet this
requirement will result in fouling of the heat exchanger channels causing poor performance,
increased pressure drop, and risk of freezing. See Colmac document 940126-0003 for more
information on strainer use in potable and source water piping.
4.1. Proper selection and sizing of Colmac heat pumps is determined by several factors including:
Size and orientation of the storage tank.
Supply water temperature.
Delivered water (tank) temperature.
Total daily volume of hot water.
Usage pattern (load profile).
Tank and line losses.
Inlet air temperature and humidity (air source heat pumps).
Source water temperature (water source heat pumps).
4.2. Consult Colmac Sales staff for assistance in correctly sizing air and water source heat pumps
and storage tanks for a given application.
5.1. The storage tank performs three important functions:
5.1.1. Allows the system to meet periods of high peak hot water demand.
5.1.2. Provides the water temperature stratification required by the HPA/HPW for
efficient operation.
5.1.3. Properly sized storage volume with correct aquastat differential setting prevents
short cycling.
5.2. HPAPro Software
5.2.1. Colmac provides at no charge to its representatives and distributors a complete
engineering software package for proper selection of air and water source heat
pump water heaters. HPAPro software allows the user to accurately size heat
pumps and matching storage tanks. The program also performs energy savings
calculations and contains detailed engineering specifications for all heat pump
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6.1. Inspection
6.1.1. Upon receipt of equipment, inspect for shortages and damage. Any shortage or
damage found should be noted on delivery receipt; this action notifies the carrier a
claim is intended to be filed. If any shortage or damage is discovered after
unpacking the unit, call the delivering carrier for a concealed damage or shortage
inspection. The inspector will need related paperwork, delivery receipt, and any
information indicating their liability for the damage.
6.1.2. Also check the electrical characteristics on nameplate of unit to be certain unit is
compatible with the power supply.
6.1.3. Remove all red shipping brackets and bracing applied to unit. Any red shipping
brackets, wood bracing or blue or pink packaging foam need to be removed prior to
machine start up. See Figure 1 below.
Figure 1 - Example of Red Shipping Bracket
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6.2. Mounting
6.2.1. Rigging: Units are crated and shipped in an upright position. After uncrating, use
of nylon slings is recommended for lifting the unit.
6.2.2. Compressor: The hermetic compressor in the heat pump is mounted on four
rubber mounts for vibration isolation. No adjustments to the four (4) bolts in the
compressor mounting feet are necessary. Remove any shipping shims if present.
In the case of scroll compressors (by Copeland), vibration isolation is by springs
which require adjustment at the time of installation.
6.2.3. Mounting: Anchor the machine in compliance to local machine mounting codes
and seismic restrictions. Failure to restrain the machine may lead to movement due
to vibration, which may result in machine damage. Machines must be oriented and
handled in the vertical upright position.
6.2.4. Curb Mount: When mounting the heat pump on a curb or on structural beams,
isolate the unit from the building with cork type pads or vibration isolation springs.
Optional Spring Isolation Kits are available for all air and water source heat pumps.
6.2.5. Machine frame: Machines are not designed to support any additional loads,
other than the machine structure. If units are to be suspended or stacked, a
separate frame work should be considered.
6.2.6. Location: Position the heat pump so the unit can be easily serviced through
access panels. Minimum distance from the unit to any wall is 24 inches (610 mm)
for this reason. On air source heat pumps, the air inlet (evaporator coil) and outlet
(fan discharge) must be unrestricted. Units with horizontal discharge fan
arrangement should be mounted with a minimum of 4 feet (1219 mm) from the fan
outlet to closest wall. Units with vertical air discharge can be located no closer than
the 24 inches (610 mm) minimum mentioned above. Reference the installation
drawing associated to the model to be installed for specific clearances.
Consideration of surrounding equipment should be accounted for in the event of
water leaks.
6.3. Electrical
6.3.1. Supply: Supply wiring is single point in the unit control panel. Fused disconnect,
if required, is supplied by others. Refer to the wiring diagram attached to the unit.
Supply wire sizing and routing shall be considered and supplied by others,
consistent with the load requirements and components of the equipment supplied
by Colmac.
6.3.2. Control: Control wiring is single point in the unit control panel. The basic heat
pump control circuit will require a normally open contact closure from the aquastat
for the heat pump run signal. Heat pumps which utilize the remote heat rejection
option will require additional control wiring from the room thermostat. Refer to the
wiring diagram attached to the unit.
6.3.3. Wire Size: Incoming line conductors must be sized according to national and
local codes for the voltage, and amperage shown on the unit nameplate. Heat
pump control leads (aquastat and room thermostat) must be a minimum of 14
AWG. Use only copper conductors for all field wiring.
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6.3.4. Source Water Circulating Pump: Source water circulating pump is to be
appropriately sized for the source water system and is to be provided by others. A
contact set will be provided in the water source heat pump (HPW) control circuit for
starting and stopping the source water pump. Pump power circuitry hardware,
circuit protection and contactors by others.
6.3.5. Consistent power quality electrical supplies shall be provided for all operating
conditions. Considerations of the equipment requiring operation in poor power
quality environments may result in additional cost to the equipment in supplemental
parts and labor, and shall be assumed by the equipment owner. Warranty
conditions shall be invalidated in poor power quality conditions.
6.3.6. The quality of electrical power may be described as a set of values of
parameters, such as:
Continuity of service
Variation in voltage magnitude
Transient voltages and currents
Harmonic content in the waveforms for AC power
Examples of possible variations:
Variations in the peak or RMS, when the RMS voltage exceeds the nominal voltage by 10
to 80% for 0.5 cycles to 1 minute, the event is called a "swell."
Sag: the RMS voltage is below the nominal voltage by 10 to 90% for 0.5 cycles to 1
Random or repetitive variations in the RMS voltage between 90 and 110% of nominal can
produce a phenomenon known as "flicker.”
Abrupt, very brief increases in voltage called "spikes," "impulses," or "surges," generally
caused by large inductive loads being turned off, or by severely by lightning impacting
voltage supplies.
"Under voltage" occurs when the nominal voltage drops below 90% for more than 1
"Overvoltage" occurs when the nominal voltage rises above 110% for more than 1
Variations in the source frequency.
Variations in the wave shape – usually described as harmonics.
Each of these power quality problems has a different cause. Some problems are a result of the
shared infrastructure.
Electrical supply quality should be provided within standard NFPA 79 as listed below:
(NFPA 79 : Voltage. The electrical equipment shall be designed to operate
correctly where the steady-state supply voltage is from 90% to 110% of the nominal
(NFPA 79 : Voltage Impulses. The electrical equipment shall be designed to
operate correctly where the supply voltage impulses do not exceed 1.5 milliseconds in
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duration with a rise/ fall time between 500 nanoseconds and 500 microseconds. A peak
supply voltage impulse shall not exceed more than 200% of the rated supply voltage
(RMS value).
(NFPA 79 : Voltage Interruption. The electrical equipment shall be designed to
operate correctly where the supply voltage is interrupted at zero voltage for not more than
3 milliseconds at any random time in the supply cycle. The time interval between
successive voltage interruptions shall be more than 1 second.
(NFPA 79 : Voltage Dips. The electrical equipment shall be designed to operate
correctly where the supply voltage dips do not exceed 20% of the peak voltage of the
supply for more than one cycle. The time interval between successive dips shall be more
than 1 second.
6.3.8. Electrical supply design reviews by certified professionals are recommended for local
conditions in consideration of the operation of the heat pump and its components.
6.4. Water Piping
6.4.1. General: For proper heat pump operation it is important to plumb the water piping
and storage tanks as indicated in the appropriate piping diagrams. Refer to
Colmac Engineering Bulletin 940126-0003.
6.4.2. All piping diagrams show non-vented pressurized systems. Vented nonpressurized systems are not recommended.
6.4.3. System piping should be plumbed and storage tanks installed in accordance with
all local and national codes that apply.
6.4.4. A Pressure Temperate (P-T) type relief valve is required on all non-vented
pressurized tank, as shown in the piping diagrams.
6.4.5. Insulation: It is highly recommended all hot water piping and storage tanks be
insulated for energy efficiency.
Outdoor applications: Fiberglass with aluminum sheathing is preferred for piping and
tanks (also sprayed foam for tanks).
Indoor applications: Fiberglass with paper sheathing is preferred for piping and tanks
(also sprayed foam for tanks). Closed cell foam is acceptable for piping and tanks
where permitted.
6.4.6. Pipe Sizing: System piping shall be sized for the minimum allowable water flow
rate required for the heat pump.
6.4.7. Existing Water Storage Tanks: The use of existing resistance heat water tanks is
permitted when the tank volume is suitable for the job application.
6.4.8. The use of existing gas water heaters and boiler as storage tanks is not
recommended due to high standby losses.
6.4.9. Using the existing water tanks without proper cleaning can result in fouling of the
internal water piping and may cause damage to the system water pump. The use
of existing water storage tanks is permitted only if measures are taken to remove
all accumulated scale deposits in the tank.
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6.4.10. Strainers should be added to all water inlet lines to filter out sediment and
particulates before they reach the Heat Pump (strainer on potable water inlet of
HPA and strainers on both potable water inlet and source water inlet on HPW).
6.5. Booster Pump
6.5.1. In piping systems where the heat pump is located far away from the storage
tanks (greater than the maximum allowable external water pressure drop), it will be
necessary to install a booster pump to maintain the minimum required flow rate.
See the pump manufacturers design data for the required flow rate and pressure.
6.6. Net Positive Suction Head (NPSH)
6.6.1. This term is defined as the water pressure required at the inlet of the pump to
cause water to flow (and prevent cavitation). NPSH can be calculated as follows:
6.6.2. NPSH = Barometric Pressure + Static Pressure on Pump Suction - Friction
losses in Suction Piping - Vapor Pressure of Water
6.6.3. Normally with non-vented, pressurized hot water systems, NPSH is high enough
to prevent cavitation. Vented, non-pressurized systems are not recommended
unless special care is taken to prevent cavitation of the water circulating pump.
Cavitation can lead to pump failure not covered by warranty.
6.7. Condensate Drain
6.7.1. During normal operation of air source heat pumps, the air drawn into the heat pump is
dehumidified producing condensate on the surface of the evaporator coil. This
condensate is collected in the coil drain pan and must be piped away to a suitable drain
system. There is a drain connection provided on all air source heat pumps for draining
the condensate from the unit. This connection is located on the underside of the heat
pump base. Pipe the condensate drain with a "P" trap to prevent drain system air from
being drawn back into the unit.
6.8. Aquastat
6.8.1. General: Heat pump water heaters are controlled by a remote aquastat, which
senses storage tank temperature and turns the heat pump on and off to maintain a
preset temperature. Typical aquastat installations include the aquastat control unit,
a sensing bulb, and a bulb well. The aquastat control will be installed and wired by
the job contractor.
6.8.2. Sensing Bulb: The use of a sensing bulb well with thermal mastic is highly
recommended for installing the aquastat sensing bulb. This will result in greater
accuracy and much faster response times than surface mounted sensing bulbs.
The location of the sensing bulb on the tank will depend on tank orientation and
piping arrangement. Refer to the piping diagrams.
6.8.3. Wiring: The aquastat will provide the heat pump run signal through a set of
normally open contacts on the aquastats output relay. As hot water is used the
storage tank temperature will fall. When the water temperature reaches the
aquastat set point (minus differential) the normally open contacts will close to start
the heat pump. Refer to the appropriate wiring diagram included with the heat
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6.8.4. Normally open contacts on aquastat must be non - powered. Damage will
result to the heat pump control circuits if voltage is applied to the control terminals.
6.8.5. Aquastat Settings: The aquastat has two adjustments, Set point and Differential,
which must be set properly by the installer for the water heating system to operate
6.8.6. The Set point is the temperature at which the aquastat contacts open and stop
the heat pump.
6.8.7. The Differential is the temperature difference between the Set point and the
temperature at which the aquastat contacts close and the heat pump starts.
6.8.8. For example, an aquastat with 140°F (60°C) Set point and 10°F (5.6°C)
Differential settings would start the heat pump when tank temperature falls to 140°
- 10° = 130°F (54.4°C), and stop the heat pump when tank temperature is brought
up to 140°F (60°C).
6.8.9. It is critical to set the Differential large enough so that the heat pump runs
for at least 10 minutes once it starts. This allows oil to circulate properly,
compressor windings to cool, Expansion Valve to modulate, etc. The minimum
Differential setting to produce 10 minutes of running time is a function of heat pump
heating capacity and storage tank volume.
6.8.10. On larger systems where multiple heat pumps are piped in parallel to a
common storage tank, an aquastat having more than one stage can be used to
sequentially add or shed units to adjust total system heating capacity to the load.
For multistage systems, use the following rules for setting aquastat set point and
differential for each stage:
Rule 1: Make set point for all stages the same. For example, if desired tank
temperature is 140°F (60°C) and the system has 3 stages, then make the aquastat
set point 140°F (60°C) for stages 1, 2, and 3.
Rule 2: Give each stage equal heating capacity. For example, in a system having 4 x
HPA/HPW, either a 2 stage aquastat with 2 x HPA/HPW on each stage or a 4 stage
aquastat with 1 x HPA/HPW on each stage could be used.
6.8.11. Colmac HPAPro Software calculates minimum aquastat differential for any
combination of heat pump capacity and tank volume.
DO NOT turn the machine on or push any of the controls until you have read and understood
the Operating Instructions.
Be familiar with all safety release switches.
Operators and supervisors should check all switches and safety features EACH DAY to
assure they are operating properly.
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Disconnect power WHENEVER any maintenance work is to be performed on the machine.
Electricity must always be disconnected when changing blower belts. Use of the "LockoutTagout" method is suggested (Figure 2).
Figure 2 - Locked and Tagged Interlock
Only qualified electricians should open control box doors. Operators and supervisory
personnel should never open the control box.
Electric power to the machine should be turned off before the electrician is allowed to open
the control box door.
If, for the purpose of locating electrical trouble, it is necessary to have the electricity on to
the control box, the electrician should use EXTREME CAUTION!
If the electrician or engineer must work on the machine with the electricity on, another
person should guard against accidental operation of the controls by others that could result
in damage to equipment or personal injury.
Damaged or worn-out electrical parts should be promptly replaced with replacements of
same rating as originals.
7.1. e-TCV (Electronic Temperature Control Valve)
7.1.1. General: Colmac heat pump models are supplied with an electronic temperature
control valve (e-TCV) as a standard feature. This valve is designed to control the
flow of water being circulated through the heat pump in response to refrigerant
condensing pressure. By slowing the flow of circulating water during periods when
the inlet water temperature to the heat pump is low (during system startup when
the system storage tank is full of cold water; for example), this control enables the
heat pump to maintain a constant, high outlet water temperature. This means
during startup or during periods of high usage the user will still be getting hot water
without having to wait for the entire water storage system to heat up.
7.1.2. The e-TCV control is actuated by refrigerant discharge pressure. The control is
mounted in the heat pump at the factory and tested prior to shipment. Installation,
operation, and maintenance of these controls are described below.
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7.1.3. The e-TCV Proportional Pressure Control is mounted in the control panel on the
heat pump and is accessed by removing the electrical access panel on the unit.
This control allows the installer to adjust the maximum heat pump condensing
pressure and so adjusting the maximum leaving water temperature. Lowering the
setpoint pressure will lower the leaving water temperature. Raising the setpoint
pressure will raise the leaving water temperature.
7.1.4. NOTE: It is important to measure the leaving water temperature during operation
after the Set Point Potentiometer has been adjusted to confirm desired outlet water
temperature. Maximum outlet water temperature will be limited by safety switches
designed to protect the compressor.
7.1.5. During operation the Proportional Pressure Control will indicate the control valve
actuator position by the LED’s on the control. One (1) lighted LED indicates a
closed valve position/low flow while all LED’s lighted indicate open valve
position/high flow. During periods of low inlet water temperatures, the control
should show closed valve position. As the tank temperature rises and inlet water
temperature to the heat pump increases, the control should show valve position
progressively opening eventually to full flow.
7.1.6. Note that the e-TCV control system is factory set such that the valve position can
never be fully closed (no flow) while energized.
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Prior to Startup
7.1.7. System Piping: Check the water system valve line-up to ensure the heat pump is
not isolated from the system and there is make-up water available.
7.1.8. Venting: Ensure the water side of the system has been vented at the system high
point and the heat pump water piping is free from air. Failure to do so can lead to
pump failure, and poor performance due to trapped air in the heat
exchangers. In the un-energized state, the e-TCV valve is in the closed position
(see Figure 3).
Figure 3 – e-TCV in Closed Position
Prior to energizing the machine, manually cycle the e-TCV valve to the open
position while purging the system of air. To do this, press the black trapezoidal
button on the side of the valve (see Figure 4), and manually move the lever (Figure
5) to the open position (see Figure 6). Purge the system of air.
Figure 4 - Button For Manual Cycling
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Figure 5 - Manually Moving the Lever
Figure 6 - e-TCV in Open Position
Do not run the circulator pump dry!
Failure of the circulator may result. Before starting the
circulator, be sure to fill the system completely with water
and fully purge ALL air from the lines.
Return the valve back to the closed position prior to energizing the machine (as shown in
Figure 3).
7.1.9. When the circulating pumps are activated with a call for heat during normal
operation, the e-TCV valve opens to 35%. This valve opening value may be
inadequate to completely purge cartridge type circulator pumps of air. See
preceding procedure for air purge process valve settings.
7.1.10. Electrical: Before energizing the heat pump, ensure all electrical connections
are tight and the electrical cabinet is in order.
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7.1.11. Check incoming voltage at the heat pump disconnect to ensure the proper
voltage is available and all phases are present.
7.1.12. Have a Digital Multi Meter available and ready to measure total amperage.
7.1.13. Gauges: A standard set of refrigeration gauges should be installed on the
suction and discharge lines to monitor the refrigeration side of the unit during
7.1.14. Three Phase Reverse Rotation: On heat pumps with three phase compressors
it is very important to check the compressor for proper rotation. This should be the
first item checked during startup.
7.1.15. When the compressor is rotating in the correct direction, on startup the
discharge pressure will begin to rise and the suction pressure fall as indicated by
the installed service gauges.
7.1.16. Use the Phase Sequence Indicator to correctly identify L1, L2, & L3 power
supply wires. The yellow light on the Phase Sequence Indicator will be illuminated
when power supply wires are properly identified. When connected to the heat
pump terminal block as labeled, the heat pump should run with correct rotation
(see wiring diagram).If on startup the suction pressure begins to rise with a
corresponding decrease in discharge pressure or if there is an objectionable noise
emanating from the compressor, then the compressor is reverse rotating.
7.1.17. If the compressor is reverse rotating, de-energize the heat pump and reverse
any (2) of the incoming power supply wires.
7.1.18. When the heat pump is reenergized, proper gauge readings should now be
7.1.19. Single phase compressors are not affected by phase reversal.
7.2. Startup
7.2.1. Energize the heat pump power source. The Power On light will illuminate.
7.2.2. If the temperature of the water in the storage tanks is less than the aquastat set
point the HW Demand light will illuminate and the time delay relay will begin to time
7.2.3. On HPW units the circulation pumps will activate, and the source water pump
contacts will close. After the time delay relay times out, the main contractor will
close to energize the compressor.
7.2.4. On HPA units, after the time delay relay times out the main contactor will close to
energize the compressor, blower, and water pump.
7.2.5. Check for proper rotation on three phase models at this time.
7.2.6. Check the line current with the amp probe, this value should be below the rated
full load current stated on the heat pump wiring diagram and the heat pump serial
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COLMAC WaterHeat
7.2.7. Monitor the temperature difference between inlet and outlet water. This value
should be between 7°F (3°C) and 10°F (7°C) if the heat pump is operating
7.2.8. On air source units (HPA), monitor the temperature difference between the inlet
and out air. The leaving air temperature should be lower than the entering air
7.2.9. On water source units (HPW), monitor the temperature difference between the
incoming and outgoing source water. The leaving water temperature should be
lower than the entering water temperature.
7.2.10. Monitor the liquid refrigerant sight glass. It will probably indicate the presence
of bubbles. These should clear within the first 30 minutes of operation. Refer to
the troubleshooting section of this manual if this condition persists.
7.2.11. The above listed conditions indicate a successful startup. Any deviations from
these normal startup conditions should be checked out in the troubleshooting
7.2.12. Continue to run the heat pump until it reaches steady state operating conditions
before filling out the startup portion of the Warranty Registration Card.
7.2.13. Warranty Registration Card: It is very important to fill out the Warranty
Registration Card completely (including startup information) and send it in to the
factory. This will allow the factory to document the successful startup.
7.2.14. NOTE: The Warranty Registration Card must be returned within (10) days of
installation to validate warranty coverage. A copy of the Warranty Registration Card
is included at the end of this manual.
7.2.15. The scroll compressors that are delivered* with threaded Rotalock shut off
valves. It is strongly recommended to periodically re-torque all fixing
connections to the original setting after the system has been put into
operation. Initial re-torqueing shall take place 7 days after initial startup.*
Proper tooling should be utilized to ensure Service Valve (King Valve) joints are not
damaged. Tooling can be purchased though Colmac to meet machine torque
Table 3 - Rotalock Torque Values
Torque Values*
Rotalock Size
3/4" - 16 UN
1-1/4" - 12 UN
1-3/4" - 12 UN
2-1/4" - 12UN
Flange w/ M16 bolts
Sight Glass
Mounting Bolts 5/16" M9
30 - 37
74 - 81
125 - 133
140 - 148
75 - 83
18 - 19
20 max
40 - 50
100 - 110
170 - 180
190 - 200
102 - 113
25 - 25.5
27 max
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COLMAC WaterHeat
* Information in section 7.2.16 from Emerson Application Engineering Bulletin
AE-1361 R1 and Copeland Scroll Compressors Replacement Guideline
C05.2.4/1007/E. Rotalocks on units larger than 4 tons.
Figure 7 – Rotalock cross section.
When opening and closing the Service Valve (King Valve) the packing gland nut
must be loosened ¼ - 1 turn before opening the valve. Turning the valve stem
without doing so may damage the packing gland nut. Make sure to tighten it
to the correct torque rating, utilizing the correct tooling. Do not use an adjustable
Wrench* 22-25ft lbs
Note: ** Emerson form 2002DS-122
7.3. Normal Operation
7.3.1. General: Once the heat pump is operating at steady state condition and the
water temperature is up to a higher value 130-140°F (52-60°C) the unit can be
checked for normal operation.
7.3.2. The suction and discharge pressures should be similar to the values shown on
the provided test report example sheet included at the end of this manual.
7.3.3. Using caution, the amperages of the compressor, blower motor, and water
pump(s) can be checked and compared to the full load current indicated on the
wiring diagrams included with the heat pump.
7.4. TXV Operation
7.4.1. General: The Thermostatic Expansion Valve (TXV) found in Colmac heat pump
water heaters acts to control the amount of refrigerant entering the evaporator coil.
The TXV responds to changing load conditions and keeps the heat pump running
at optimum efficiency.
7.4.2. Another function performed by this valve is to prevent liquid refrigerant from
returning to the compressor and causing damage.
7.4.3. Superheat: The TXV is controlled by Suction Superheat which is defined as the
temperature difference between Suction Gas Temperature (measured directly) and
Saturated Suction Temperature (found on P-T table using measured Suction
7.4.4. It is very important to insure the HPA/HPW heat pump is operating with the
proper amount of Suction Superheat.
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To Calculate Suction Superheat:Read Suction Pressure using standard refrigeration
service gauges. Find R-134a Saturated Suction Temperature (SST) from
Table 4 or Table 5 below.
Measure Suction Gas Temperature (SGT) directly using a surface
temperature probe at the TXV bulb.
Calculate: Suction Superheat = SGT - SST
Table 4 - R-134a Pressure-Temperature, IP units
Table 5 - R-134a Pressure-Temperature, SI units
7.4.5. NOTE: Suction Superheat should be between 10°F and 15°F (5.6°C and 8.5°C)
during normal operating conditions.
7.4.6. When the heat pump is equipped with a field adjustable TXV, Suction Superheat
can be changed if necessary using the following procedure:
Using two (2) wrenches, remove the TXV service cap (opposite the diaphragm
end of the valve).
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COLMAC WaterHeat
To increase Suction Superheat, turn the adjusting stem CLOCKWISE.
To decrease Suction Superheat, turn the adjusting stem COUNTERCLOCKWISE.
When adjusting the TXV, make no more than one turn of the stem at a time and
observe the change in superheat closely to prevent over-shooting the desired
As much as 30 minutes may be required for the new balance to take place after
an adjustment is made.
After completing the adjustment, replace and tighten the service cap.
7.4.7. NOTE: The TXV used on Colmac heat pumps uses an M.O.P. (Maximum
Operating Charge) to prevent excessive suction pressures during periods of very
high entering air temperature. Superheat adjustments can only be made when the
Suction Pressure reads 60 psig or less.
7.5. Time Delay Relay
7.5.1. General: All Colmac heat pumps incorporate a time delay relay in the heat
pump electrical control circuit. The time delay relay reduces the possibility of
compressor short cycling. Compressor short cycling is when the compressor
attempts to start too often in a short period of time. The result of this frequent
starting would be to overheat the compressor motor windings because of
insufficient runtime.
7.6. Enunciator Lights
7.6.1. There are several enunciator lights (number varies by model) which indicate the
Power On - Illuminates when power is applied to the heat pump.
HW Demand - Illuminates when the water temperature has fallen below the
aquastat set point.
AC Demand - On units with remote heat rejection, this light illuminates when the
room temperature has fallen below the room thermostat set point.
High Press Fail - Illuminates when the high pressure cutout switch receives a
high pressure signal.
Low Press Fail - Illuminates when the low pressure cutout switch receives a low
pressure signal.
Phase Failure – Illuminates when any one of the following conditions exist:
Low Voltage
High Voltage
Phase Imbalance
Loss of Phase
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COLMAC WaterHeat
Phase Reversal
Oil Press Fail – Illuminates when there is insufficient oil pressure for safe
compressor operation.
Low Flow (source water) – Illuminates when there is insufficient source water
flow (only for water source units).
Low Temp (source water) – Illuminates when the source water temperature falls
below 37°F (2.7°C) to prevent freezing of the source water components and
piping (only for water source units).
7.7. Status Lights
7.7.1. Depending on model there are three status lights on the exterior of the heat
pump (some skinned units with lift off panels).
The red light indicates an alert or error.
The amber light indicates a call for heat.
The green light indicates the unit is running and producing hot water.
7.8. Safety Switches
7.8.1. The refrigerant system has (2) safety cutout switches which will prevent the heat
pump from running in the following cases:
Low Pressure Cutout - Stops the heat pump when refrigerant suction pressure
decreases to 5 psig. The switches normally open contacts close to energize a
latching relay. This relay energizes the Low Press Fail light and de-energizes the
main contactor.
High Pressure Cutout - Stops the heat pump when refrigerant discharge pressure
increases to 400 psig. The switches normally open contacts close to energize a
latching relay. This relay energizes the High Press Fail light and de-energizes the
main contactor.
7.8.2. Resetting the unit: The above conditions generally indicate the heat pump needs
attention from a qualified service technician.
7.8.3. The above conditions will lock out the heat pump electrically until the main power
has been de-energized and reenergized.
DO NOT turn the machine on or push any of the controls until you have read and understood
the Operating Instructions.
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COLMAC WaterHeat
Be familiar with all safety release switches.
Operators and supervisors should check all switches and safety features EACH DAY to
assure they are operating properly.
Disconnect power WHENEVER any maintenance work is to be performed on the machine.
Electricity must always be disconnected when removing lint screen or changing blower belts.
Use of the "Lockout- Tagout method is suggested (Figure 2).
Figure 8 – Locked and Tagged Interlock
Only qualified electricians should open control box doors. Operators and supervisory
personnel should never open the control box.
Electric power to the machine should be turned off before the electrician is allowed to open
the control box door.
If, for the purpose of locating electrical trouble, it is necessary to have the electricity on to the
control box, the electrician should use EXTREME CAUTION!
If the electrician or engineer must work on the machine with the electricity and/or air on,
another person should guard against accidental operation of the controls by others that could
result in damage to equipment or personal injury.
Damaged or worn-out electrical parts should be promptly replaced with replacements of
same rating as originals.
8.1. Air Filter (Air Source Units)
8.1.1. To ensure proper operation the heat pump air filters should be cleaned on a
regular basis. Dirty filters that restrict air flow across the evaporator coil will reduce
water heating capacity and may adversely affect heat pump components.
8.1.2. The standard air filter can be cleaned with a mild soap and water. Care should
be taken to avoid damaging the filter with a high pressure water stream. The larger
optional filter requires replacement when fouled.
8.1.3. Air Filters are recommended on all air source heat pumps.
8.2. Evaporator Coil (Air Source Units)
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COLMAC WaterHeat
8.2.1. Drain pan: The drain pan and drain tube should be cleaned and checked
regularly to prevent fouling.
8.2.2. P-trap: The P-trap should also be checked regularly. If a Colmac P-trap was
used, it can be cleaned via a removable plug.
8.2.3. Evaporator fins should be maintained in straightened condition and free of
contaminates that could contribute to moisture retention and premature failure. A
regular schedule for vacuuming the exterior coil surface should be implemented.
This is especially important if air filters are not employed.
8.3. Blower Belts and Bearings (Air Source Units)
8.3.1. Lubrication of the pillow block bearings and drive belt inspection should take place at
regular intervals on all HPA units larger than 4 tons equipped with centrifugal fans. Refer
to Table 6 for lubrication intervals.
Table 6 - Lubrication Intervals
Bearing Operating
Up to 122
Up to 156
Up to 212
Up to 248
Up to 302
Environmental Condition
12 months
6 months
3 months
6 weeks
2 weeks
6 months
2 months
2 weeks
1 week
3 days
Washdown or Extremely Dirty
3 months
1 month
1 week
3 days
8.3.2. Compatibility: Do not mix greases! When two incompatible greases are mixed,
the mixture will either harden and will not release any of the oil, or soften and
releases all of the oil. In either case, the bearing is not effectively lubricated.
Colmac Industries uses and recommends: Lubrication Engineers 1250
ALMASOL High Temperature Lubricant.
8.3.3. The bearing seals should be maintained to ensure long life. Pushing excessive
lubrication into bearing can cause seal (B in Figure 9) displacement, damaging ball
lubricity capacity. The lubrication tubes on the bearings are pre-charged and
require very little pressure to advance lube. Excessive lube pressure to the
lubrication line will displace the tube from bearing fitting due to hydraulic pressure,
and damage the access port. Take caution not to damage lubrication tubing (see
Figure 10 and Figure 11).
Figure 9 - Standard Single Lip Seal
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COLMAC WaterHeat
Figure 10 - Excessive Lubrication Damage
Figure 11 - Excessive Lubrication Damage
8.3.4. Mounting Instructions (Accu-Loc)
1. Inspect the Shaft
a. Measure the shaft to ensure it is within the recommended tolerances per
Table 7.
Table 7 - Recommended Shaft Tolerances
Inch Size Shafting
Metric Size Shafting
Shaft Diameter up to 1-15/16"
Nominal to -0.0005"
Shaft Diameter up to 45 mm
Nominal to - 0.013 mm
Shaft Diameters 2" to 4-7/16"
Nominal to - 0.0010"
Shaft Diameters 50 mm to 140 mm
Nominal to - 0.025 mm
b. Check for any nicks or burrs that might percent the bearing from sliding on
the shaft easily.
c. Clean the mounting surface, and then apply a film of light weight oil.
2. Place the bearing on the shaft
a. Do not hammer the bearing onto the shaft
3. Bolt the housing to the mounting surface
a. Use plain washer under the mounting bolt heads to span the slot width.
b. The bearing and shaft must be aligned to within 2 degrees.
c. Rotate the shaft to ensure it rotates smoothly and freely.
4. Fasten the unit to the shaft
a. Place the locking collar on the tangs of the inner bearing ring with the
chamfered corner (see Figure 127) on the bore of the collar towards the
bearing. The collar is stamped with the word “FRONT” on one side. This
side should be facing away from the bearing and should be readable to
the installer.
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COLMAC WaterHeat
Figure 127 - Collar Placement
b. Tighten the capscrew to the recommended tightening torque per Table 8
using a variable torque wrench.
Table 8 - Recommended Tightening Torque of Accu-Loc Collar Capscrews
Applicable Bearing #
Recommended Tightening Torque (in-lb)
Black Oxide Finish
Kanigen Corrosion Resistant
8.4. Source Water Strainer (Water Source Units)
8.4.1. Y-strainers are to be flushed periodically to remove any particulate that may
accumulate. Frequencies of flushes are dependent on water quality.
Electrical Connections
8.4.2. When performing periodic maintenance and while the heat pump is de-energized
all electrical connections should be checked to ensure they are tight. Loose
electrical connections can cause high resistance connections that will lead to
failure of the terminal.
8.5. Safety
8.5.1. De-energize all electrical power sources before attempting to service any heat
8.5.2. Before brazing on any piping system, ensure the system is depressurized and
vented to atmosphere.
8.6. Refrigerant
8.6.1. The refrigerant used in the HPA/HPW heat pumps is R-134a. This refrigerant is
an HFC and therefore has no Ozone Depletion Potential.
8.6.2. Only qualified refrigeration technicians should perform maintenance on any
refrigeration system and they must comply with any local or national codes that
8.7. Refrigerant Oil
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COLMAC WaterHeat
8.7.1. Colmac heat pumps use R-134a refrigerant and POE (polyolester) oil. This oil is
very hygroscopic (will absorb moisture from air) and therefore care should be taken
to minimize the time the system is open to the atmosphere during repairs. Make
sure all the needed components and supplies are available prior to starting any
repair procedure.
8.7.2. Do not mix refrigeration oils. Use only the oil that is named on the compressor
label. Refer to compressor manufacturer specifications for type and volumes of
required oil.
8.7.3. POE* = Copeland® Ultra 22 CC, Copeland® Ultra 32 CC, Copeland® Ultra 323MAF ,Mobil EAL™ Arctic 22 CC or Uniqema RL32-3MAF
*Emerson Form No. 93-111R17
8.8. Refrigerant Gauge Ports
8.8.1. Standard access valve ports (with valve cores) are provided on the suction and
discharge lines. The ports will accommodate standard refrigeration gauges and
can also be used for evacuation and charging. Replace port caps after access.
8.9. Access Panels
8.9.1. During normal operation all panels should be in place and secured with fasteners
to prevent unauthorized access.
8.10. Troubleshooting
8.10.1. Use Table 9 to diagnose heat pump problems.
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COLMAC WaterHeat
Table 9 - Colmac HPA/HPW Troubleshooting Chart
#1 Unit not running,
no hot water.
High pressure light
Aquastat setting too
Faulty high pressure
Loss of water supply
to the HPA/HPW.
Pump has stopped
Low pressure light on.
Aquastat has failed
Faulty low pressure
Fan motor is not
operating properly.
Loss of refrigerant.
Flow through
evaporator restricted
or blocked.
No lights on.
Reduce aquastat
temperature setting.
Replace high
pressure switch.
Check water flow to
the HPA/HPW.
Check pump wiring.
Replace pump if
Replace aquastat.
Replace low pressure
Check fan motor
wiring. Replace motor
if necessary.
Check refrigerant
piping for leaks.
Add refrigerant until
sight glass is clear.
Remove any
material which may
be blocking
evaporator coil.
Clean coil if
necessary with a
warm soapy water
solution. Back flush
brazed plate version
Air filter is blocked
with dirt.
Remove and clean air
filter with a warm,
soapy water solution.
Filter dryer restricted
or blocked.
Replace filter dryer.
TXV has failed in
closed position.
Clean and/or replace
TXV internals if
necessary. Check
power element and
replace if necessary
Main fuses failed.
Replace fuses.
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COLMAC WaterHeat
#2 Unit runs but no
hot water (or reduced
Suction pressure reads
low with clear sight
Flow through
evaporator restricted or
Air filter is blocked with
Fan motor is not
operating properly.
Suction pressure reads
low and sight glass
shows bubbles.
Discharge pressure
reads high
Low refrigerant charge.
Filter dryer restricted or
Air trapped in the water
tube of the condenser.
Water pump beginning
to fail (insufficient water
Air or other noncondensable in the
refrigerant system.
Remove any material
which may be blocking
evaporator coil. Clean
coil if necessary with a
warm soapy water
solution. Back flush
brazed plate version
Remove and clean air
filter with a warm soapy
water solution.
Check fan motor wiring.
Replace motor if
Check refrigerant piping
for leaks. Add
refrigerant until sight
glass is clear.
Replace filter dryer
Compressor failure.
Bleed all air from the
water system.
Check operation of
pump and replace if
Remove refrigerant from
the HPA/HPW.
Evacuate and recharge
with R-134a.
Remove refrigerant until
normal operating
condensing pressures
are observed.
Flush water piping and
condenser with acetic
acid solution.
Replace compressor.
Compressor internal
overload (tripped).
Allow compressor to cool
and restart.
Three phase
compressor is running
Switch any two (2)
supply voltage wires to
the HPA/HPW.
Unit is overcharged with
Condenser surface
Compressor runs but
suction and discharge
pressures are equal.
Fan and pump run but
compressor not
Compressor runs noisy
and suction pressure
reads higher than
discharge pressure.
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COLMAC WaterHeat
8.11. Leak Repair/Brazing
8.11.1. Care should be taken to use good refrigeration service techniques when
repairing the heat pump.
8.11.2. Always follow all of the component manufacturers’ instructions when installing
or servicing individual components.
8.11.3. When repairing water system leaks it will be necessary to isolate the heat pump
from the water system and drain the heat pump piping before brazing.
8.11.4. When replacing any refrigeration system component it is recommended the
filter drier be replaced also.
8.11.5. On all copper to copper joints 15% silver solder should be used.
8.11.6. On all copper to steel or copper to copper plated steel joints 56% silver solder
with paste flux should be used, insulate behind braze to reduce heat transfer to
other components. Overheating of Condenser plates, Service Valves (King
Valves), TXV Valves, will cause failure. Wet ragging techniques should be
*Emerson form 2002DS-122
8.11.7. The following general procedures can be used for replacing refrigeration system
8.12. Removal of existing refrigerant charge
8.12.1. Ensure the proper replacement parts are on hand before starting any repair
8.12.2. If heat pump has a refrigerant charge present then that charge needs to be
recovered according to local and national laws using appropriate recovery and
recycling equipment.
8.12.3. Typically this refrigerant is recovered to a refrigerant bottle. If the refrigerant is
suspected to be contaminated it must be recycled (cleaned) at an appropriate
facility for future use. If the refrigerant is not contaminated and good recovery
techniques are used, it can be placed back into the original equipment after repairs
are complete.
8.13. Removal of defective components
8.13.1. The refrigeration system piping should remain vented while brazing to prevent a
buildup of pressure.
8.13.2. Use a nitrogen gas purge when brazing if possible to prevent the formation of
internal scale in the system piping.
8.13.3. When brazing at high temperatures it is necessary to protect the components
that are not being removed from the high heat to prevent damage. This can be
done by using wet rags to wrap the heat sensitive components. You can also
utilize small pieces of sheet metal to act as barriers between the torch flame and
any other item that needs to be protected (insulation, cabinet sheet metal, or
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COLMAC WaterHeat
wiring). Usually it is not necessary to protect the defective component from the
8.13.4. After the brazing preparation is complete identify the joints/connections where
the component/piping will be separated.Apply heat at the first joint and at the same
time grasp the component or pipe with a pair of pliers or similar tool so that the
component can be pulled free from the pipe when the solder melting temperature
has been reached.
8.13.5. After the first connection has been separated then proceed to the second joint
and repeat the above step.
8.13.6. When the TXV is being removed the ¼ inch equalizing tube must also be debrazed from the TXV.
8.13.7. Care should be taken not to let foreign materials or water enter any of the open
piping or component ends.
8.13.8. If pipes are required to be cut, use a pipe cutter to sever pipe. Saws
produce shavings that can travel through the system under pressure and foul
otherwise functional components.
8.14. Installation of new components
8.14.1. Check the new component/assembly for proper fit up by holding it up to the free
pipe ends.
8.14.2. Use wet rags to completely wrap the new component. This will prevent damage
due to overheating. Do not allow any water from the wet rag to enter any of the
replacement components/assemblies.
8.14.3. Braze in the new component using proper brazing techniques. It may be
necessary to heat a previously soldered connection so the new component will
slide onto it.
8.14.4. Apply heat to the first connection and then apply the silver solder to the entire
pipe circumference so a leak free braze joint is formed.
8.14.5. Repeat the above step for the second connection.
8.14.6. Repeat the above step for the TXV equalizing tube if the TXV is being replaced.
8.14.7. After brazing is complete, allow the piping and components to return to ambient
temperature (this can be hastened by applying wet rags).
8.15. Leak Test
8.15.1. After the system has returned to ambient temperature proceed with leak testing.
8.15.2. Attach a set of standard refrigeration gauges to the suction and discharge
access valves.
8.15.3. Pressurize the system with 400 psig of pure nitrogen gas via the “common”
gauge port (gauge valves open).
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COLMAC WaterHeat
8.15.4. Isolate the Nitrogen supply and note the pressure reading.
8.15.5. Allow the system to remain in this condition while performing a leak check with
a soapy water solution.
8.15.6. Apply the soapy water solution to all connections that were previously worked
on as well as the hose/gauge connections. Bubbles will form in the soapy water
solution wherever a leak is located.
8.15.7. If leaks are found then the nitrogen must be bled off and the gauges removed
for additional brazing. Be sure to check any solder connections that may have
been loosened during the initial brazing operation.
8.15.8. If no leaks are found utilizing the soapy water solution then allow the system to
remained charged with nitrogen for a minimum total of (3) hours (preferably
overnight). At the end of this time period, check the pressure reading of the
gauges. They should be unchanged from the previous readings (except for
changes due to a change in ambient temperature).
8.16. Evacuation
8.16.1. Prepare an evacuation pump for evacuation of the system by ensuring there is
fresh refrigeration oil in it and the connections are in good working order. There
should also be a vacuum gauge in line with the system. This gauge should be able
to be isolated from the evacuation pump to determine the system vacuum level.
8.16.2. Connect the evacuation pump to the “common” gauge connection and energize.
8.16.3. Allow the evacuation pump to run for several hours.
8.16.4. Check the vacuum gauge reading. If the reading is less than 500 microns,
isolate the evacuation pump from the system. Allow the reading to stabilize. If the
vacuum maintains a reading below 500 microns for 10 minutes, close the gauges
isolation valves. Shutdown the evacuation pump, then proceed to charging.
8.16.5. If the reading goes above 500 microns, continue to pump down. If the vacuum
reading cannot be maintained below 500 microns after pumping down overnight
then the system will need to be checked for leaks again.
8.16.6. If replacing refrigeration on a unit that has been run, use best practices to
ensure refrigeration is evacuated from the oil.
8.17. Refrigerant charging
8.17.1. Ensure the gauge isolation valves are closed.
8.17.2. Locate a bottle of R-134a refrigerant with enough refrigerant to completely
charge the system (charge quantity is indicated on the unit nameplate).
8.17.3. Attach one end of a refrigerant charging hose to the refrigerant bottle.
8.17.4. Attach the other end to the “common” gauge port of the charging gauge set (do
not tighten this connection at this time).
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8.17.5. Crack open the bottle isolation valve to allow a small quantity of refrigerant
vapor to purge the line. This vapor should be escaping from the “common” gauge
port connection. After a few seconds of purging, tighten the hose connection on
the “common” gauge port.
8.17.6. The refrigerant charge should be added to the unit through the suction gauge
and port connection.
8.17.7. If the heat pump is being charged for the first time, break the vacuum (see
Section 8.17) with refrigerant vapor. Energize the unit. Add refrigerant vapor while
the unit is running until bubbles in the sight glass disappear.
8.17.8. Return the system to the normal operating condition and then proceed with
system startup as discussed previously.
8.18. Testing
8.18.1. Whenever major service work is performed on the heat pump it is necessary to
test the unit for proper performance.
8.19. Refrigerant Pressure Switch Replacement
8.19.1. If the suction and discharge pressure safety switch fails in any of the following
ways, the switch must be replaced.
Contacts fail to operate at the set point.
The contacts do not reset at the correct value.
The switch body fails mechanically resulting in a leak.
8.20. Switch Replacement
8.20.1. NOTE: Observe all local and national codes when servicing refrigeration
8.20.2. De-energize heat pump power supply and allow the unit to cool to ambient
8.20.3. Remove the wiring harness (¼ inch (6 mm)) wire disconnects) from the switch
8.20.4. Using (2) wrenches, loosen the switch body on the Schrader valve. Spin the
switch off of the Schrader valve. The valve core will close to keep the refrigerant in
the line.
8.20.5. Check to ensure the correct replacement switch is being used.
8.20.6. Spin on the new switch by hand until the connection is sealed then tighten using
(2) wrenches.
8.20.7. Replace the wires on the switch terminals.
8.20.8. Energize the heat pump and resume normal operation.
8.21. Pump Replacement
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COLMAC WaterHeat
8.21.1. De-energize heat pump power supply and allow the unit to cool to ambient
temperature. Close the heat pump isolation valves and disconnect the piping at
the pipe unions. Allow the water lines to drain.
8.21.2. Remove the water pump access panel.
8.21.3. Disconnect the supply wires in the water pump connection box and remove the
supply wiring harness.
8.21.4. If the pump motor has burned out or if the motor canister flange is not sealing to
the bronze pump body, the entire motor assembly will need replaced.
8.21.5. If the impeller is damaged, only the pump cartridge needs replaced.
8.21.6. Remove the affected component and replace it with the new repair part.
Ensure the correct replacement part is being used.
8.21.7. Install the wiring harness into the connection box and connect the supply wires
to the appropriate motor leads.
8.21.8. Reconnect the pipe unions and open the isolation valves. Vent water system
piping to remove all air.
8.21.9. Check the water pump for leaks and then replace the access panel.
8.21.10. Re-energize heat pump and resume normal operation.
8.22. Fan Motor Replacement
8.22.1. If the blower fan motor has failed, use the following replacement procedure.
8.22.2. Ensure the correct replacement part is on hand before starting this procedure.
8.22.3. De-energize the heat pump power supply and remove the unit top. On ceiling
suspended units, the heat pump must be lowered to floor level to gain access for
this repair.
8.22.4. Disconnect the supply wiring from the motor.
8.22.5. Remove the motor/belly band assembly from the unit.
8.22.6. For motors that are mounted using a wire type belly band, measure and note
the belly ban position on the original motor then loosen the belly band fasteners.
Place the belly band on the replacement motor on adjust to match the original
position then tighten securely.
8.22.7. Install the new motor/belly band assembly on the blower housing making sure
the blower wheel is properly aligned. Test blower wheel for proper alignment and
adjust as necessary.
8.22.8. Re-connect the supply leads to the motor leads.
8.22.9. Re-energize heat pump and resume normal operation.
8.23. De-liming
940126-0001 Rev L
COLMAC WaterHeat
8.23.1. General: Liming is the fouling of the heat exchanger surface with calcium
8.23.2. Under normal circumstances the low surface temperatures in the heat pump
condenser together with high water velocity and turbulence suppress the formation
of scale and fouling.
8.23.3. A severely scaled condenser will cause the heat pump to run with excessively
high Head Pressure while at the same time exhibiting a very large difference
between condensing temperature and leaving water temperature.
8.24. De-liming Procedure:
8.24.1. Never perform de-liming with the heat pump attached to the hot water system.
This will introduce the cleaning solution and all dissolved scale into the water lines.
8.24.2. Only qualified service technicians should perform the following procedure.
8.24.3. Avoid breathing the fumes! Do not get solution in eyes! Use adequate
8.24.4. De-energize the heat pump and then disconnect the power supply.
8.24.5. Close water valves that isolate the heat pump from the hot water system.
Disconnect the heat pump from the system water piping at the pipe unions near the
water inlet and outlet.
8.24.6. Move the heat pump unit to an area that is well ventilated, has a floor drain, and
a source of water.
8.24.7. Pour approximately 3 gallons (11.3 liters) of household (white) vinegar in a
plastic or metal bucket. Elevate the bucket to a position higher than the heat pump
inlet and then place both heat pump pipes (hot water inlet and outlet) in the bucket.
8.24.8. NOTE: The heat pump will require flexible hoses or special piping for this step.
A throttling valve should be added to the outlet hose or pipe to control the amount
of vinegar flowing through the heat pump.
8.24.9. Disconnect the HPA/HPW fan and compressor wires from their respective
contactors so that only the water pump inside the heat pump will run, circulating the
vinegar in and out of the bucket.
8.24.10. Apply power to the pump and throttle the outlet valve to allow vinegar to
circulate at a rate of approximately 2 gallons per minute (7.0 l/m).
8.24.11. Household vinegar is a mild acid. It is in a diluted form as sold in the store so
it is limited in descaling capabilities. If the solution in the bucket is discoloring or
scale particles are observed, it is cleaning satisfactorily. Continue de-liming action
for 1/2 hour or until foaming stops then turn off the heat pump.
8.24.12. Areas with particularly hard water may require with a stronger chemical. Food
grade cleaners bearing USDA acceptance seals are available through your local
water softener dealer or refrigeration supply house.
940126-0001 Rev L
COLMAC WaterHeat
8.24.13. The procedure for using the stronger cleaner is the same as given above;
however, the cleaner container will provide additional information and instructions
on the particular product's characteristics and usage. These instructions must also
be followed.
8.24.14. When De-liming process is completed, the heat pump should be flushed with
clean water to remove residual scale and cleaning solution.
8.25. Flushing Procedure
8.25.1. Thoroughly rinse out the bucket and refill with clean water. Place the heat
pump hoses/pipes back into the bucket and run for 10 minutes. At end of 10
minutes, shut the heat pump off.
8.25.2. After rinsing the bucket out, place the bucket under a fresh water tap and let the
water run into bucket at about the pumping rate of the heat pump.
8.25.3. Place the heat pump inlet hose/pipe in the bucket. Position the outlet hose/pipe
to discharge into a drain.
8.25.4. Apply power to the pump and allow fresh water to circulate through the heat
pump for five (5) minutes or until discharged water is clear. Shut off the heat
8.25.5. Reconnect the heat pump to the water tank and purge air from the piping.
8.25.6. Reconnect wiring to fan and compressor.
8.25.7. Reconnect power to the heat pump and resume normal operation.
940126-0001 Rev L
COLMAC WaterHeat
Colmac HPA/HPW Owner Warranty Registration Card
Important Product Warranty Information
Owner must complete and return to Colmac Industries Inc. within 10 days of start
up for validation.
Owner's Name:_________________________________________________________________
State/Province: ______________________PostalCode:______________Country:____________
Unit Model #: ________________________Unit Serial #: _______________________________
Installer Name:_________________________________________________________________
Address:___________________________________________ City: ______________________
State/Province: ____________________Postal Code: ___________Country: _______________
Yes No
___ ___
___ ___
___ ___
___ ___
___ ___
___ ___
___ ___
Was there any visible shipping damage?
This unit was started only after completion of construction.
The installer has checked this unit for proper installation and operation.
The owner has accepted a maintenance or service agreement from the installer or service
The dealer/installer included one year service in his proposal.
The unit was purchased with an extended compressor warranty.
Was the unit started by Colmac or a Colmac approved Technician?
HPA/HPW Performance Test Data (Installer to complete)
___ ___ Does the Service Correspond to the unit name plate?
Is the unit mounted level?
Is the condensate line trapped?
Fill Drain pan, does it drain freely with the machine running?
Are all electrical connections tight?
1. Line Voltage _______L1-L2______L2-L3______L1-L3
2. Total Amps _______L1______ L2_______L3
3. Inlet Air Dry Bulb Temp. ________C° ________F°
4. Inlet Air Wet Bulb Temp. ________C° _______ F°
5. Inlet Air Relative Humidity, % ________%
6. Leaving Air Dry Bulb Temp. ________C° ________F°
7. Source Water Temp. ________C° _________F°
940126-0001 Rev L
COLMAC WaterHeat
8. Leaving Source water Temp. _______C° ________F°
9. Potable Inlet Water Temp. ________C° ________F°
10. Potable Outlet Water Temp. ________C° ________F°
11. Tank Aquastat Model ___________________________
12. Tank Aquastat Set point Temp. ________C° ________F°
13. Tank Aquastat Differential ________C° ________F°
14. Head Pressure __________kPa __________psig
15. Suction Pressure __________kPa __________psig
16. Suction Gas Temp. ________C° ________F°
17. Discharge Gas Temp. ________C° ________F°
18. Liquid Line Temp. ________C° ________F°
19. Electrical Heater Voltage _______L1-L2______L2-L3______L1-L3
20. Amp draw across each phase at each heating element
Owner's Signature: _______________________________________Date: _______________________
Owner's Printed Name: _______________________________________
Installer's Signature: ______________________________________Date: _______________________
Installers Printed Name: _______________________________________
940126-0001 Rev L
COLMAC WaterHeat
While the following information is not required to validate the warranty of your Colmac HPA/HPW heat
pump, we would appreciate you taking a few minutes to furnish us with additional data to help us provide
our customers with the best products and service that we can. Thank you.
THIS IS A ___New Installation ___Retrofit ___Replacement
If replacement, what type of system was replaced? (brand, type,
Why did you replace your existing water heating system with a Colmac HPA/HPW unit?
___ Old system needed to be replaced
___ Desirable energy savings
___ Needed hot water with cool air benefit
___ Other:________________________________________
Why did you purchase a Colmac HPA/HPW heat pump?
___ Advice from Dealer
___ Advice from friend
___ Personal Knowledge
___ Energy Savings
___ Other:_________________________________________
Where did you first see or hear about HPA/HPW heat pumps?
___ Magazine
___ Trade Show
___ Dealer Display
___ Friend
___ Utility Company
___ Direct Mail
Did you have any installation problems?
___ Yes _____________________________________________
___ No
___ Don't Know
Is your HPA/HPW heat pump operating satisfactorily?
___ Yes
___ No ______________________________________________
Other Comments:
940126-0001 Rev L
COLMAC WaterHeat
Colmac warrants that the product manufactured by it will be of the kind and quality described in its
specifications, and will be free of defects in workmanship and material. Should any failure to conform to this warranty
appear within a period of one year from the date of original installation or eighteen months from date of shipment to the
purchaser, whichever comes first, Colmac shall, upon prompt written notification thereof correct such non-conformity at
its option, by repair or replacement F.O.B. factory, of the defective part or parts.
In no event shall Colmac be responsible for providing working access to the defect, the removal, disassembly,
replacement or reinstallation of any product, materials or structures to the extent necessary to permit Colmac to perform
its warranty obligations, or transportation costs to and from the Colmac factory. The conditions of any tests shall be
mutually agreed upon and Colmac shall be notified of and may be present at all tests that may be made.
To validate a claim, Colmac reserves the right to require that defective parts be returned to the factory,
transportation charges prepaid.
Filters, fan belts, refrigerants, pads, covers, oil or other consumables are not included. This warranty does not
apply to products or parts damaged by accidents, abuse, improper installation, lack of proper maintenance,
unauthorized alterations, misapplications, improper applications, fire, flood, or acts of God. Furnishing of parts as
described above shall constitute fulfillment of all Colmac obligations with respect to the warranty and replacement parts
will be warranted only for the unexpired portion of the original warranty.
Products supplied by Colmac, but manufactured by others, are warranted only to the extent of the
manufacturer's warranty.
The remedies provided above are the purchaser's sole remedies for any failure of Colmac to comply with its
obligations. Correction of any non-conformity in the manner and for the period of time provided above shall constitute
complete fulfillment of all the liabilities of Colmac whether the claims of the purchaser are based in contract, in tort
(including negligence) or otherwise with respect to or arising out of the product furnished hereunder.
Colmac, its contractors and suppliers shall not be liable in contract, in tort (including negligence and strict
liability) or otherwise for damage or loss of other property or equipment, loss of profits or revenue, loss of use of
equipment or power system, cost of capital, cost of purchased or replaced power or temporary equipment (including
additional expenses incurred in using existing facilities), claims of customers of the purchaser or for any special,
indirect, incidental, or consequential damages whatsoever.
The remedies of the purchaser set forth herein are exclusive and the liability of Colmac with respect to any
contract, or anything done in connection therewith such as the performance of breach thereof, or from the manufacture,
sale, delivery, resale, or use of any equipment covered by or furnished under the contract, whether in contract, in tort
(including negligence and strict liability) or otherwise, shall not exceed the price of the equipment or part on which such
liability is based.
P.O. Box 72, Colville WA 99114-0072 USA; Phone 509-684-4505; Fax 509-684-4500
940126-0001 Rev L
What do I do if something goes wrong with
my Colmac Water Heating Heat Pump?
Call Colmac Service
A Colmac service technician will help you by offering troubleshooting advice to determine specifically what
may be wrong.
Often times Colmac can remedy the problem over the phone.
Remember, Colmac technical support over the phone is free!!
Can I get on-site help at location?
I would like a
Colmac Technician
I have a local
Colmac factory rep
“COLMISSION” is an on site
visit to help solve problems
and train operators/staff.
If your WHHP is less than
one (1) year old, please
have your contractor
contact Colmac for a “Field
Repair Authorization”.
Call for pricing and to set up
a schedule for your on site
Only pre-authorized field
repair procedures and costs
are eligible for
What if I need parts to fix my problem?
If the problem may be caused by
“workmanship” or a “defect in
material” AND your machine is less
than one (1) year old…
Or if you purchased an extended
compressor warranty.
Your parts may be covered under
Colmac’s service department will
issue you a quote, and you need to
send a purchase order for the parts
in question.
Colmac will issue RMA (Return
Material Authorization) information
to you.
If your machine is older than
one (1) year, or the parts in
question are “consumable/
wear” parts...
Are belts, air filters, covered
under warranty?
Sorry, but consumable/wear
parts like these are not
covered under warranty.
Your parts may be purchased
and are usually shipped the
same day to you.
Parts are shipped based on your
requested shipping method.
Overnight shipping is usually
available, but remember, you will
need to pay the shipping costs...
(even on warranty parts)
You return the problem parts back to
Colmac; remember to include the
same RMA information Colmac
issued you earlier!
Colmac will inspect the returned
parts and determine the root cause
of the failure.
If the failure is deemed to be a defect in
“workmanship” or “material”…
Colmac will credit your account the amount of
the purchase order you issued earlier!
If the failure is deemed NOT to be a defect in
“workmanship” or “material”…
Colmac will not issue a credit for the parts not
qualifying for warranty replacement.
Colmac reserves the right to change product design and specifications without notice.
For more information on Colmac products call us at 1-800-926-5622 or visit us online at:
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