Space Pak SCM Instruction manual

Copyright 2012 Mestek, Inc.
SCM2-1212
W30-WG0593
IN UNITED STATES: 260 NORTH ELM ST. WESTFIELD, MA 01085 800-465-8558 / FAX [phone]
IN CANADA: 7555 TRANMERE DRIVE, MISSISSAUGA, ONTARIO, L5S 1LR [phone] / FAX [phone]
SECTION 1: READ BEFORE PROCEEDING
Model SCM overview .................................................................. 2
SECTION 2: SPECIFICATIONS AND RATINGS
SECTION 3: DIMENSIONS
SECTION 4: LOCATION & MOUNTING
Prepare the unit .......................................................................... 5
Location ...................................................................................... 5
Handling ...................................................................................... 5
Mounting pad .............................................................................. 5
SECTION 5: GLYCOL/WATER SYSTEM
Glycol/water system design ......................................................... 8
Glycol/water system installation .................................................. 8
SECTION 6: ELECTRICAL CONNECTIONS
Overcurrent protection & wire sizing ........................................... 9
Optional low ambient adjustment ................................................ 9
SpacePak heat pump/chiller wiring ............................................. 9
Multiple air handler applications .................................................. 9
SECTION 7: START-UP AND TEST
BEFORE starting the unit ............................................................ 11
Start the SpacePak heat pump/chiller ......................................... 11
Anti-freeze cycle ......................................................................... 11
24-Hour follow-up ........................................................................ 11
SECTION 8: TROUBLESHOOTING
SECTION 9: MAINTENANCE
Glycol/water mixture ................................................................... 13
Perform annual inspection .......................................................... 13
Preparing the SCM for shut down ............................................... 13
To restart after shutdown ............................................................ 13
SECTION 10: REPLACEMENT PARTS
SECTION 11: PERFORMANCE DATA
3-Ton SpacePak chiller ............................................................... 15
5-Ton SpacePak chiller ............................................................... 15
SECTION 12: LIMITED WARRANTY
MODEL SCM
INSTALLATION,
OPERATION
& MAINTENANCE
MANUAL
Air To Water Heat Pumps
Reverse Cycle Chillers
3 and 5 Ton
For information not included in this
manual, see the following: This manual
includes only basic information for instal-
lation, operation and maintenance of
SpacePak air to water heat pumps. For
more advanced applications and informa-
tion not shown in this manual, contact
SpacePak Technical Support for assis-
tance and supplemental instructions. Call
413-564-5530 in Westfield, MA or visit our
website at www.spacepak.com to send an
e-mail or review technical literature.
Qualified installer only —
This product must be installed
only by a qualified service techni-
cian. The installation must be
done using recognized industry
practices, and in compliance with
this manual and all applicable
codes. Failure to comply could
result in death, serious injury or
substantial property damage.

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Hazard definitions
The following terms are used throughout this manual to bring
attention to the presence of potential hazards or to important
information concerning the product.
Indicates an imminently hazardous situation which,
if not avoided, WILL result in death, serious injury or
substantial property damage.
Indicates an imminently hazardous situation which,
if not avoided, COULD result in death, serious
injury or substantial property damage.
Indicates an imminently hazardous situation which,
if not avoided, MAY result in minor injury or property
damage.
Used to notify of special instructions on installation,
operation or maintenance which are important to
equipment, but not related to personal injury
hazards.
Model SCM overview
The SPACE PAK Model SCM Heat pump/chiller is a self
contained reverse-cycle heat-pump that provides a continuous
supply of heated or chilled water for various purposes, such as:
residential or small commercial building heating and cooling;
and specialty applications, such as computer room cooling or
industrial/agricultural conditioning and dehumidification.
Model SCM Chillers are available in three- and five-ton nominal
capacities. Both use the same general design and operating
principals.
Each chiller contains TWO isolated refrigeration systems of
equal size to cool or heat the delivered water supply. The two
systems can operate individually or in tandem to achieve 50%
or 100% capacity. The major components of each system are:
• A hermetically sealed refrigeration compressor & motor.
• An outside coil to reject heat (in cooling) or absorb heat (in
heating) from the surrounding ambient air.
• A fan and motor to force air over the outside coil; a shell-
and-tube refrigerant-to-water heat exchanger to absorb heat
(in cooling) or supply heat (in heating) to the delivered water
flow.
• An electronic expansion valve to throttle the refrigerant flow
in both heating and cooling modes of operation, responding
to varying load on the system.
• Additionally, each system contains a reversing valve (to
select between heating and cooling operation) and sensors
and safety circuits to monitor and protect the equipment from
potentially damaging or dangerous operating conditions.
A single water circuit connects both internal heat exchangers,
and contains sensors to measure entering and leaving water
temperatures. A mechanical flow switch safety ensures
continuous water flow while either of the two refrigerant
systems is operating. All components are contained within a
supporting structure and enclosure sufficient to allow stand-
alone outdoor installation in all temperate climates.
All operation and protections are managed by a microprocessor
controller which operates the individual systems, determines
all operating parameters, and monitors the condition of each
system. A simple interface communicates with the indoor air
handler, heat exchanger, or other load.
Codes and electrical requirements
• This product must be installed in accordance with all
applicable codes. Where instructions in this manual differ
from specific local requirements, defer to the local codes.
• The electrical installation must also comply with the latest
edition of: in the U. S. — National Electrical Code ANSI/
NFPA No. 70; in Canada — CSA C22.1 Canadian Electrical
Code Part 1. Wiring must be N.E.C. Class 1. Use only copper
wire, rated for 120°F and sized for the load listed in this manual.
• Electrical shock hazard — Disconnect all electrical power
before servicing the unit. Also, the unit must be grounded in
accordance with the Electrical Code listed above.
Refrigerant
• Refrigeration system is factory charged with R410A refrigerant,
and requires no additional service during installation. Any
repair, diagnosis or maintenance service to the refrigeration
system must be performed by a qualified technician. No
alternate refrigerants, lubricants or additives are approved for
this unit. Any use of alternate or non-approved materials in the
refrigeration system may result in personal injury or equipment
damage, and will void the manufacturer’s warranty.
Liquid side
The fluid in the liquid side of the Model SCM
must be an anti-freeze/water mix.
• The antifreeze percentage must be at least 10%. Follow
guidelines in this manual to find the required antifreeze mix
for the application. Thoroughly flush the system before filling.
• The system must be supplied with a pump sized to provide
the minimum flow rates specified in this manual. Pump
selection must consider the pressure loss through the system
and its components plus the pressure loss through the SCM’s
heat exchanger and internal components. The pump must be
rated for use with chilled water/glycol mixture.
• Install a y-strainer at the liquid input of the heat pump as
shown in this manual to prevent damage to the heat
exchanger from sediment.
• DO NOT use for potable water heating. The single-wall
heat exchanger is not suitable for the application.
Ambient limits
• See information in this manual for heating and cooling
performance versus ambient temperature.
• For applications requiring cooling at outdoor temperatures
below 55°F, contact SpacePak Technical Support for
assistance.
• DO NOT disconnect power in cold temperatures. Power
must be on to allow the anti-freeze cycle to operate.
SCM controller
• The SCM electronic controller is factory configured. DO NOT
adjust the control settings. If special operating characteristics
are required, contact SpacePak Technical Support for
availability and instructions.
Failure to comply with all of the guidelines
BELOW could result in death, serious injury or
substantial property damage.
Section 1: READ BEFORE PROCEEDING

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Standard equipment
• Heat pump/chiller, including two refrigeration systems,
factory-programmed controller, fans and all required internal
components
• Powder-coated enclosure
• Auxiliary electric immersion heater (3 KW, 230V/1/60) —
requires separate electrical power circuit, 15-amp minimum
breaker
Additional components required
• Pump and piping by others
• Expansion tank, properly sized for system volume
• SpacePak Chiller Interface Module
Figure 2 Model SCM coding
Item Units SCM-036 SCM-060 Item Units SCM-036 SCM-060
Cooling capacity (Note 2) Btuh / KW 34,000 / 10.0 46,000 / 13.5 Supply voltage VAC 230/1/60 230/1/60
Heating capacity (Note 3) Btuh / KW 44,000 / 13.0 60,000 / 17.0 Running current,
cooling (Note 1) Amps 17.6 26.4
Fan speed RPM 850 850 Running current,
heating (Note 1) Amps 13.1 21.3
Noise level dB(A) 56 56 MCA (Note 1) Amps 19.7 30.3
Water volume Gallons 2 2.5
Supply connection Inches NPT 1 1 Return connection Inches NPT 1 1
Minimum supply
temperature °F 36 36 Maximum supply temperature °F 125 125
Minimum flow GPM 7 10 Maximum flow GPM 12 15
Pressure drop at
minimum flow Feet WC 8 17 Pressure drop at maximum flow Feet WC 21 28
Net weight Lbs 337 386 Operating weight Lbs 354 407
Shipping weight Lbs 346 395 Shipping dimensions Inches 47 x 18 x 60 47 x 18 x 60
Note 1: Electrical ratings DO NOT include water pump amp draw. This pump is supplied by the installer. Add the current draw of the pump to
the values listed above. Adjust the MCA accordingly.
Note 2: Performance at 95° ambient temperature, 47° water
Note 3: Performance at 45° ambient temperature, 115° water
Typical model S C M 060 A 4
Position 1 2 3 4 5 6 7 8
Designation Unit Type Capacity Series Refrigerant
type
Values SCM = SpacePak Heat Pump/Chiller Module
036 = 3 ton nominal
060 = 5 ton nominal
A= Series “A” 4= R410A
Examples
SCM-036-A-4 = 3 ton nominal, series A, using R410A referigerant, SpacePak Heat Pump/Chiller Module
SCM-060-A-4 = 5 ton nominal, series A, using R410A referigerant, SpacePak Heat Pump/Chiller Module
Section 2: Specifications and ratings
Figure 1 Model SCM rating data

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Section 3: DIMENSIONS
Figure 3 Model SCM dimensions (ALL DIMENSIONS IN INCHES)
Model
A B D D1 D2 E F G H J K W W1 W2
Leg
height
Front to
return
Cabinet
depth
Mounting
lug
depth
Mounting
lug
centers
Bottom
to
return
Bottom
to
supply
Base to
bottom edge
of lower fan
Overall
Height
Return
connec-
tion
Supply
connec-
tion
Overall
width
Mounting
lug
centers
Lug
center
to edge
SCM-036 1 10 17 3
/
417 3
/
815 3
/
45 1
/
215 1
/
425 53 1" NPT 1" NPT 43 3
/
827 1
/
27 15
/
16
SCM-060 1 10 17 3
/
417
3
/
815 3
/
45 1
/
215 1
/
425 53 1" NPT 1" NPT 43 3
/
827 1
/
27 15
/
16

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Section 4: LOCATION & MOUNTING
Failure to comply with all of the guidelines
IN THE FOLLOWING could result in death,
serious injury or substantial property damage.
The installation must comply with all applicable
local codes.
Prepare the unit
• Inspect the unit for shipping damage. DO NOT use if there is
a risk that the damage could affect unit operation.
• Make sure all required components are available.
• Install optional immersion heater, if used. See instructions
provided with the heater.
Location
• DO NOT locate where the unit could be sprayed by sprinklers.
• DO NOT locate near swimming pools, spas or any location
that could cause chlorine or other contaminant to enter the
unit.
• DO NOT locate where water run-off from adjacent structures
could impinge on the unit.
• Maintain the clearances shown in Figure 5.
• LOW AMBIENT conditions — Contact SpacePak Technical
Support to obtain low ambient adjustment instructions if
cooling operation below 55°F is required.
• CORROSIVE ENVIRONMENTS — Do not install the unit in
an area subject to sea air or other potential corrosive
contaminants.
• INDOOR INSTALLATION — If the unit is installed inside a
building, the building must be equipped with air openings
sufficient to ensure free discharge of heated (or cooled) air
generated by the heat pump/chiller. All clearances must be
maintained to ensure free air flow into and out of the
enclosure. Make sure no other equipment located in the
space will be affected by the unit’s air flow.
Handling
• See Figure 4.
• Place padding at pressure points to prevent damage to the
enclosure.
• Use caution when handling. The unit is heavy and could
cause severe injury or damage if dropped or handled
incorrectly.
Mounting pad
• The SpacePak heat pump/chiller must be mounted on a
level corrosion- and weather-resistant mounting surface,
preferably concrete. The structural support must be
suitable for the operating weight of the unit and attached
components, its mounting pad, snow loading and any other
expected loads.
• The mounting pad must not be attached directly to a structure
where noise transmission would be objectionable.
• Vibration isolators supplied with the chiller may be installed
when desired to reduce transmitted vibration.
• The unit must be bolted securely to the pad. Where required
by local jurisdiction, the mounting must also be analyzed for
seismic loading capability.
• The mounting must ensure that there will be no debris
accumulation which might block air flow through the
enclosure openings. The lower edge of the lower fan
opening must be above the typical snow line, including
allowance for drifting.
• There must be no accumulation of water that could reach the
bottom of the unit’s enclosure.
Minimum clearances (inches)
STUV
20 59 40 20
Figure 4 Handling with cables
Figure 5 Maintain clearances below

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1 SpacePak heat pump/chiller
2 Pump (by installer) — see instruc-
tions in this manual for sizing infor-
mation
3 Drain valve
4 Isolation valve, typical — install
where shown (2 required)
5 Y-strainer — must be installed
where shown to prevent sediment
from damaging or clogging the
chiller heat exchanger
6 Expansion tank (diaphragm or
bladder type)
7 Air separator with automatic air
vent — install in two locations, as
shown
8 Purge valve (external valve
required only when purge valve is
not integral to the air handler
9 Air handler — Make sure the
chiller/heat pump is sized for the
air handler load
10 Supply connection, 1" NPT
11 Return connection, 1" NPT
12 Pressure gauge
13 Balancing valves (2 per air handler)
— see Figure 7, page 7
14 3-way valves (1 per air handler) —
see Figure 7, page 7
15 (Not shown) — Install a hose bib
valve at a convenient location in
the system. Use this valve to fill
the system with the required glycol/
water mixture.
16 Manual air vent.
Figure 6 SpacePak Chiller with single air handler (see page 7 for instructions)
Section 5: Glycol/water system

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Figure 7 SpacePak Chiller with two air handlers (parallel piping) (see page 7 for instructions) — see legend on page 6
Section 5: Glycol/water system (continued)
Glycol/water system design
1. SpacePak heat pump/chiller capacity — The SCM capacity
is reduced as glycol percentage increases. Multiply the rated
capacity by the multiplier listed in Figure 8, page 8.
2. Select the recommended piping layout from either Figure 6,
page 6 or Figure 7, page 7.
For system designs not covered in this manual,
contact SpacePak Technical Support for further
information.
3. Other equipment in the system — Make sure the system
design meets the requirements of air handlers, boilers and
other components in the system.
4. Existing systems — Modify existing system piping and compo-
nents as needed to comply with the recommendations in this
manual.
5. Automatic fill — SpacePak recommends NOT installing an
automatic fill line except where required by local codes.
Where required, connect the fill line to the expansion tank.
When an automatic fill system is installed, the
cooling fluid (Glycol/water) must be inspected at
least every three months, or whenever a leak is
detected, to ensure the proper glycol concentration
is maintained.

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Section 5: Glycol/water system (continued)
Figure 8 SCM glycol concentration (10% min, 50% max)
Ethylene glycol % 10 20 30 40 50
Min ambient temp, °F 23 14 2 –13 –36
SpacePak capacity multiplier .98 .96 .93 .91 .89
Pressure drop multiplier (cooling) 1.06 1.12 1.16 1.25 1.36
Pressure drop multiplier (heating) 1.06 1.12 1.16 1.22 1.28
Propylene glycol % 10 20 30 40 50
Min ambient temp, °F 26 18 8 –7 –29
SpacePak capacity multiplier .99 .98 .96 .93 .88
Pressure drop multiplier (cooling) 1.10 1.20 1.34 1.50 1.65
Pressure drop multiplier (heating) 1.10 1.20 1.34 1.46 1.50
6. Size the piping and select the system pump using the flow
rate and pressure drop given in Figure 1, page 3. Adjust the
pressure drop through piping and chiller using the glycol
correction multipliers in Figure 8, page 8.
7. System volume and expansion volume – To ensure smooth
temperature control and minimize cycling of refrigeration
system, all installations must have total volumes equal to or
greater than five gallons per nominal ton of the smallest staging
increment. In other words, a three ton chiller is comprised of
two, equal, 1 ½ ton refrigeration systems, each of which can
operate independently. Therefore the minimum total system
volume is 5x1.5=7.5 gallons. Similarly, a five ton chiller has
two 2 ½ ton systems, so the minimum system volume is 5x2.5,
12.5 gallons. Multiple chiller installation that are operating in
a staged configuration follow the same rule, so that only one-
half of the smallest chiller tonnage needs to be considered.
Additionally, the system requires an expansion volume (air)
of one gallon of open volume for every twenty gallons of
actual system volume (not just minimum volume) A typical
multiple chiller installation will generally have a volume
far greater than the minimum required, and it is this entire
volume that must be considered when sizing the expansion
tank. Note that the nominal expansion tank volume is not the
same as the expansion volume. If the actual air volume is not
published, consider it to be no more than half the nominal
volume. As an example, a single five ton chiller requires a
minimum of 12.5 gallons of system volume. When the system
installation is complete, the total liquid volume of plumbing,
air handlers and heat exchanger is twenty gallons. A three
gallon nominal expansion tank is selected, which provides 1
½ gallons of expansion volume, but also adds 1 ½ gallons
to the system volume. Therefore the total volume is now
21.5 gallons, 21.5÷20=1.08 gallons, the minimum expansion
volume. The 1 ½ gallons of available expansion volume is
greater than 1.08, so the 3 gallon expansion tank and the
entire system, comply with these guidelines.
8. Air vents — Locate high-efficiency air vents as shown in the
piping to prevent air from pocketing.
Glycol/water system installation
1. Obtain all components specified in Figure 6, page 6 or
Figure7, page 7. Make sure all components and piping
comply with applicable local codes.
DO NOT use galvanized pipe anywhere in the
system. Galvanizing will react with the glycol and
can cause glycol degradation and sludge in the
system.
1. Charge the expansion tank to 15 PSIG (with no water or
pressure in the system).
2. Install the system piping. DO NOT connect the SpacePak
unit to the system piping until the system has been cleaned
as required below.
Clean the system
1. The SCM must NOT be connected to the system during this
process.
2. Connect a hose from a fresh water supply to the system
fill hose bibb. The hose bibb valve (not shown in piping
diagrams) should be located low in the system near to the
SpacePak connection.
3. Open the purge valve, (may be inside the air handler) while
slowly filling the system. Close the valve when air is removed
from the system and water begins to flow out of the valve.
4. Fill the system with fresh water and run water until the system
has been thoroughly flushed clean.
Pressure test the system
1. Add water to the system as needed to raise the pressure to
35 PSIG (verify that all system components are suitable for
this pressure). Verify that the pressure remains constant for
at least one hour. Locate and correct any leaks.
2. After successfully testing,drain the system and removed the
fresh water hose.
Insulate the piping
1. After testing and draining the system, apply pipe insulation.
Fill system with glycol/water mixture
1. Calculate the system volume. (Find the SCM water volume
in Figure 1, page 3.)
2. See Figure 8, page 8 for required glycol concentration for
the minimum expected outside temperature.
3. Obtain the required volume inhibited glycol/water solution
premixed or mix in a clean container. (The glycol must
contain an inhibitor to prevent metal corrosion.)
4. Pump the glycol/water solution into the system, allowing air
to escape through the purge valve(s).
5. After filling the system, sample the system fluid and verify
glycol and inhibitor percentages, following instructions
provided with the glycol.

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The electrical installation must comply with
the latest edition of: in the U.S. — National
Electrical Code ANSI/NFPA No. 70; in
Canada — CSA C22.1 Canadian Electrical
Code Part 1. Wiring must be N.E.C. Class 1.
Use only copper wire, rated for 120°F and
sized for the load listed in this manual.
Electrical shock hazard — Disconnect
all electrical power before servicing the
unit. Also, the unit must be grounded in
accordance with the Electrical Code listed
above.
Overcurrent protection & wire
sizing
• Protect each circuit with a breaker or fuse rated for
the load given in Figure 1, page 3.
The electrical loads given in Figure 1,
page 3 allow for a pump load of no more
than 5 amps at 110 VAC (2.5 amps at
230 VAC). If the pump load exceeds this,
provide a separate power source to the
pump. DO NOT feed power to the pump
from the SpacePak air handler panel.
• Provide a separate power source and overcurrent
protection for the immersion heater. Refer to the
Figures 11 and 12 of this manual for detailed wiring.
Optional low ambient
adjustment
• If cooling is desired in low ambient conditions,
follow the instructions supplied by SpacePak
Technical Support.
SpacePak heat pump/chiller
wiring
The SpacePak SCM chillers require a dry
contact (relay) signal to enable and select
between heating and cooling modes.
They will not operate on the 24V signals
from typical thermostats or air handlers.
Connecting 24V to either of these points
will result in erratic operation and may
cause significant component damage.
• Connect
single air handler to chiller as shown in
Figure 9, page 9.
• Connect
multiple air handlers to chiller via
SpacePak Chiller Interface Module as shown in
Figure 10, page 10.
• See Figure 12, page 12, for chiller electrical ladder
diagram.
Section 6: Electrical connections
Figure 9 SpacePak Heat Pump/Chiller field wiring — SINGLE air
handler (See Figure 12, page 12 for ladder wiring diagram)

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Figure 10 SpacePak Heat Pump/Chiller field wiring — Multiple air
handlers (see Figure 12, page 12 for ladder wiring diagram)
Section 6: Electrical connections (continued)
Multiple air handler applications
• See Figure 10, page 10.
•
For multiple air handler applications, provide a zone
valve or pump to control water the flow to the air
handler.
• When the zone thermostat activates the SCM,
the valve will be activated by the SpacePak air
handler.
• The total zone control load must not exceed
20 VA at 24 VAC. If a larger valve or zone pump
is used, it must be switched by a power relay
controlled from the 24 VAC output of the air
handler.
• Refer to manual supplied with SCC-5 module for
connection and operational details.

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Figure 11 SpacePak Heat Pump/Chiller — Pictoral wiring diagram
Section 6: Electrical connections (continued)

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Figure 12 SpacePak Heat Pump/Chiller electrical ladder diagram
Section 6: Electrical connections (continued)

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BEFORE starting the unit
Electrical shock hazard — Disconnect all electrical
power before proceeding with the following.
Verify that the system and all components have been
installed in accordance with this manual and all applicable
codes and instructions.
Inspect the SpacePak heat pump/chiller and all other system
components. All components should be in good condition
and operational.
Inspect the water piping for any signs of leakage.
Repair all system leaks. Leakage will cause pressure
to drop, preventing the heat pump/chiller from
operating. Leaks also allow introduction of excess
make-up water, whether filled automatically or
manually.
Check system pressure. The pressure should be at least
15 PSIG with heat pump/chiller not in operation.
Check all wiring connections to ensure terminal connections
are tight and all wiring is in place.
Start the SpacePak heat pump/chiller
Start in cooling mode.
1. Apply power to the unit
2. The display (Figure 13, page 14) (should show the start
sequence — uC2, then 2.0, then the current water tempera-
ture. No other symbol should appear.
3. When the display shows only temperature, lower the
thermostat setpoint below the current room temperature.
4. This begins a call for cooling, and the pump symbol will begin
to flash.
5. After 1 to 2 minutes, the pump symbol will change to constant
display, and the pump will begin circulating.
6. Assuming the water is outside of the cooling temperature
range (above 42 deg) the refrigeration system will initiate
and the 1, or 3, or both numerals will begin flashing.
7. After 1 to 2 minutes, the 1, or 3, or both numerals will change
to constant, the compressor symbol will turn on and one or
both compressors will start.
8. Observe for any alarms, errors, or faulty operation (noises,
vibration, etc)
9. When operation is deemed satisfactory, raise the thermostat
set-point or turn it off.
10. The pump will run for approximately two minutes after the
compressor shutdown.
Start in heating mode.
1. When the pump has stopped, change the thermostat to
Heating (if applicable) and raise the set point above current
room temperature.
2. This initiates a call in Heating mode. The pump symbol will
begin flashing.
3. After 1 to 2 minutes, the pump symbol will change to constant
display, and the pump will begin circulating.
4. Assuming the water is outside of the heating temperature
range (below 120 deg) the refrigeration system will initiate
and the 1, or 3, or both numerals will begin flashing.
See the attached illustration; note this is not intended to include
all components in the system, just the minimum to properly
purge air from the chiller.
1. With the chiller isolated and dry, valves A & B closed, charge
the “system”(that is, all the plumbing not shown), and remove
as much air as possible through the air separator.
2. Apply a static pressure to the system, with all pumps off, of
15-25 PSI.
3. Very gradually open the lower ball valve, B, to allow water
under pressure to begin to fill the chiller from the bottom.
4. Crack the manual vent valve until you hear air escaping.
5. Allow the water to continue to fill the chiller, displacing air.
This should go very slowly, and could take a minute or more.
6. When all the air has been displaced and a steady stream of
water is flowing out of the vent valve, fully open ball valve B.
7. Open ball valve A, a small amount of air might escape the
vent valve from the chiller supply line.
8. When all the air has escaped, close the vent valve.
Note, this procedure fills the chillers in the opposite direction of
normal flow, so it must be done when all pumps are off.
PURGE VALVE
(MANUAL)
DRAIN VALVE
A
B
Section 7: Start-up and test

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Figure 13 Controller display
Section 7: Start-up and test (continued)
5. After 1 to 2 minutes, the 1, or 3, or both numerals will change
to constant, the compressor symbol will turn on and one or
both compressors will start.
6. Observe for any alarms, errors, or faulty operation (noises,
vibration, etc).
Anti-freeze cycle
1. Should the water temperature drop to 34°F during periods
of non-use, the pump will start and the antifreeze heater (if
connected) will energize and continue to operate until the
temperature reaches 38°F.
2. If the water temperature continues to fall and reaches 33°F,
the Alarm symbol and Fault Code AL will be displayed,
and the unit will automatically start in heating mode. It will
continue to run until the water temperature reaches 38°F.
3. NOTE: This provides the maximum level of protection in all
cases, but may use energy unnecessarily when a suitable
concentration of glycol anti-freeze is installed. When freeze
protection is sufficient, these value can be adjusted to
lower temperatures. Contact technical support for guidance
in re-configuring these parameters, however it must be
understood that the installer is responsible for ensuring
sufficient freeze protection to the lowest temperature
allowed.
24-Hour follow-up
Approximately 24 hours after start-up and testing, return to the
installation to verify proper operation. Perform the following
checks.
Check system pressure. Add additional glycol/water mixture
if needed to restore pressure. (Pressure can drop as air is
removed from the system by the air vents.)
Sample the glycol/water mixture in the system. Verify inhibitor
and glycol levels.
Inspect the piping and components to ensure there are no
leaks. Repair any leaks immediately.
Close the isolation valves on either side of the y-strainer at
the SpacePak heat pump/chiller return connection. Remove
the screen and inspect for sediment. Clean if necessary.
• If the strainer has become clogged with sediment,
determine whether the system needs to be drained,
cleaned and re-filled. Excessive sediment accumulation
in the strainer will reduce flow and cause the unit to shut
down.
Cycle the system on heating and cooling. Verify that all
components operate correctly.

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Section 8: Troubleshooting
Figure 14 Troubleshooting suggestions
Condition Possible Causes Verification Solution
Unit will not start
Incorrect power supply Check power supply Supply correct power
Loose or broken wires Check wiring Repair or replace wiring
Circuit breaker interrupted Check for short
Compressor running - insufficient cooling/
heating
Insufficient pipe insulation Check insulation Add/repair insulation
Dirty coil Check coil Clean Coil
Low water flow Look for alarm symbol and FL fault code
Clean strainer screen
Clear blockage
Remove air in piping
Verify operation/condition of water pump
High compressor discharge pressure in
cooling Dirty coil Check coil Clean Coil
High compressor discharge pressure in
heating Low water flow Measure water flow through heat exchanger
Flow should be a minimum of 10 GPM for
SCM060 or 8 GPM for SCM036
Low compressor suction pressure in
cooling
Insufficient/no water flow Look for alarm symbol and FL fault code
Clean strainer screen
Clear blockage
Remove air in piping
Verify operation/condition of water pump
Cooling operation in low ambient Confirm outdoor ambient is lower than
typical for cooling operation, e.g. <55°
If low ambient cooling is desired, contact
Technical Support for procedure to modify
fan operating parameters.
Compressor will not run
Power supply failure Supply correct power
Failed compressor contactor Replace contactor
Loose power cable Check power cable Tighten power cable
Compressor limit exceeded
Check for compressor symbols 1 and/or
3. If symbol is displayed but compressor
is inactive, thermal overload has been
tripped.
This will reset, however root cause must
be determined
Incorrect return water temperature setting Check return water temperature setting Adjust return water temperature setting
Low glycol/water flow Look for alarm symbol and FL fault code
Clean strainer screen
Clear blockage
Remove air in piping
Noisy compressor Liquid returning to compressor Replace compressor
Compressor failure
Fan will not run Fan relay failure Replace fan relay
Fan motor failure Replace fan motor
Compressor runs - no heating/cooling
No refrigerant charge Check for leaks Add appropriate refrigerant
Damaged heat exchanger Check for glycol/water leaks and/or
refrigerant leaks Replace heat exchanger
Compressor failure Replace compressor
Low outlet glycol/water temperature in
cooling
Improper temperature control setting Check cooling temperature setpoint and
differential
Contact Technical Support for instructions
to reset cooling setpoints
No load/rapid temperature drop
Ensure compressors are allowed to
run a minimum of three minutes before
reaching desired temperature
Verify cooling fuction when there is
sufficient heat load to allow continuous
operation.

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Condition Possible Causes Verification Solution
Low outlet glycol/water temperature in
heating
Dirty coil, damaged or improperly
operating fans
Visually inspect coil condition and fan
operation
Clean coil, repair fan blade or motor as
necessary.
Extremely low ambient temperature Heating performance falls considerable
as temperatures drop below 20-25°F
Install supplemental heating for extreme
low ambient conditions.
Low glycol/water flow
Damaged or blocked plumbing or air
handler
Check for blockage and/or air in piping,
check operation/condition of water pump
Clean strainer screen
Clear blockage
Remove air in piping
Defective or improper pump Verify pump operation/condition. Measure
water flow through the heat exchanger
Replace or re-size pump to obtain a
minimum of 10 GPM for SCM060 or 8
GPM for SCM036
Section 8: Troubleshooting (continued)
Figure 14 Troubleshooting suggestions (continued)
Figure 15 Fault codes
FAULT
CODE MALFUNCTION REASON ACTION
E1 Water Inlet Temperature Sensor Failure Short Circuit or Sensor Open Check/Replace Sensor
E2 Evaporator #1 Water Outlet Temperature
Sensor Failure
Short Circuit or Sensor Open Check/Replace Sensor
E3 Outside Coil #1 Temperature Sensor Failure Short Circuit or Sensor Open Check/Replace Sensor
E4 Ambient Temperature Sensor Failure Short Circuit or Sensor Open Check/Replace Sensor
E5 Delivered Water Outlet Temperature Sensor
Failure
Short Circuit or Sensor Open Check/Replace Sensor
E6 Evaporator #2 Water Outlet Temperature
Sensor Failure
Short Circuit or Sensor Open Check/Replace Sensor
E7 Outside Coil #2 Temperature Sensor Failure Short Circuit or Sensor Open Check/Replace Sensor
AL Anti-Freeze Cycle Error / Cooling Water Temperature has Fallen Below
Antifreeze Protection Setpoint
Check Flow Rate
Check For Blockage in Piping
FL Flow Switch Error Inadequate Water Flow Rate Verify or Increase Glycol Concentration and Contact Mestek
Technical Support for Instructions to Lower Alarm Setpoint
HP1/HP2 High Pressure Alarm
System1/System2
Discharge Pressure Exceeds Maximum
Allowable
Cooling Mode:
Check for Dirty Coil
Check for Restricted Air Flow
Check for Excessive Ambient Temperature
Heating Mode:
Check for Sufficient Water Flow Rate
LP1/LP2 Low Pressure Alarm
System1/System2
Suction Pressure Below
Minimum Allowable
Cooling Mode:
Check for Sufficient Water Flow Rate
Heating Mode:
Check for Dirty Coil
Check for Restricted Air Flow
Check for Low Ambient Temperature

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Glycol/water mixture
The water system must contain a mixture of
inhibited glycol and water with thermal protection
sufficient for the coldest expected temperature for
the installation. The inhibitor level can degrade over
time, and may need to be adjusted periodically. The
inhibitor is essential to prevent the glycol from
accelerating corrosion of metal components in the
system. The glycol and inhibitor levels must be
checked regularly (no less than once annually).
The minimum allowable concentration of glycol is
10% by volume in all installations.
Automotive glycol is not suitable for use in th Chiller
system. Over time it may leave deposits which will
degrade Chiller performance and damage pumps
or other devices in the system.
Use only ethylene glycol or propylene clycol
mixtures specifically labeled for boiler or hvac use.
1. At least once annually, sample the system fluid to verify that
the glycol concentrations meets the minimum value given in
Figure 8, page 8. Also test the inhibitor concentration. Add
glycol and inhibitor as needed to return the system to the
correct concentrations.
2. Perform any and all other tests as recommended by the
anti-freeze manufacturer’s instructions in order to ensure
optimal performance and maintain warranty protection on all
installed components.
Check operating pressure
1. Check the glycol/water system pressure. Operating pressure
should be between 15 and 25 PSIG. Adjust fluid volume if
needed to restore pressure.
2. If pressure is low, check system for evidence of leaks. Repair
all leaks immediately.
Perform annual inspection
Electrical shock hazard — Disconnect all electrical
power before proceeding with the following.
1. At least once annually, perform a complete inspection of the
system, including at least the following.
Inspect the SCM for signs of dirt or debris accumulation.
Remove any debris and notify the building owner that the
unit must be kept clean and unobstructed.
Inspect glycol/water system piping and components. Repair
or replace any defective components. Repair all leaks
immediately.
Close the isolation valves on either side of the y-strainer at
the SpacePak heat pump/chiller return connection. Remove
the screen and inspect for sediment. Clean if necessary.
• If the strainer has become clogged with sediment,
determine whether the system needs to be drained,
cleaned and re-filled. Excessive sediment accumulation
in the strainer will reduce flow and cause the unit to shut
down.
Inspect all wiring and wiring connections. Tighten connections
if needed. Correct any problems found.
Check the fuses or breakers to ensure they are correctly
sized and properly installed.
Clean the SCM heat exchangers and air openings.
Cycle the system on heating and cooling. Verify that all
components operate correctly.
Preparing the SCM for shut down
DO NOT turn off power to the SCM heat pump/
chiller in the winter or any time when there is a
possibility of freezing. Power must be ON for the
automatic anti-freeze operation to occur. See
information below for preparing the unit for shut
down.
1. When the water temperature drops below 34°F during
periods of non-use, the pump will start and the antifreeze
heater (optional, when installed) will energize and continue
to operate until the temperature reaches 38°F.
2. If SCM must be turned off or left idle during periods when
freezing is possible, one of the following must be done:
a. Verify that sufficient glycol solution is present to protect
against most extreme anticipate conditions
b. — OR — Drain chiller and external piping completely
To restart after shutdown
1. If unit was drained, refill.
2. Follow start up procedure on page 13.
Section 9: Maintenance

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Section 10: Replacement parts
Figure 16 Replacement parts
PART NUMBER DESCRIPTION VENDOR PART NUMBER
SCS036 SCS060
20000-320009 Carel Temperature Sensor NTC015WP00 (IP68,-55F to 212F, 5 Ft., 10K Ohm)
20000-360006 Compressor Contactor HCC-1NU04AA
45W14RWG0061-01 Transformer, 24V BE321650GBA0015
2000-3136 Fan Motor On/Off Contactor (Carel) CONVON/OFF
2000-3137 Carel Expansion Module MCH2000020
2000-3138 Carel Controller MCH2000010
2000-3157 Soft Start PCB 2000-3157
2000-3501 Fan Motor Compacitor CBB61 (35μF/450VAC)
2000-3603 Low Pressure Switch H20PS (0.02MPa/0.15MP)
2000-3606 Water Flow Switch HF68P/1"NPT
2000-3619 Pump Control Relay JQX-105F-4 (220-240V, 30A)
2000-3711 Transformer, 24V 41X26.5F (220~230VAC,50/60Hz, 11.5VAC,0.6A)
2001-3605 High Pressure Switch H20PS (3.2MPa/4.4MPa)
2001-3608 Overload Pressure Switch H20PS (2.8MPa/3.6MPa)
2003-1402 Electronic Modulating Valve SPF-16D32 (9.5kW)
2004-1437 4-Way Valve C03C01S/SHF-9H-35U / STF-0203G (R410A)
3404-3301 Fan Motor GAL045H6-225-K01/ YDK-45X-6D
3500-2701 Propeller Fan 440×152 AS+20%GF
20000-110058 Compressor ATH290RN-C9LU
20000-110068 Compressor PA200M2CS-3MUU1
2000-3504 Compressor Capacitor CBB65 (35μF/450V)
2000-3505 Compressor Capacitor CBB65 (50μF/450V)
35018-120010 Heat Exchanger GAH04-CM×2
35018-120012 Heat Exchanger GAH03-CMF×2
35036-120011 Condenser Coil - Left 3 rows, Φ7.94mm
35036-120012 Condenser Coil - Right 3 rows, Φ7.94mm
40000-120006 Condenser Coil - Left 2 rows, Φ7.94mm
40000-120007 Condenser Coil - Right 2 rows, Φ7.94mm
20000-000025 Immersion Heater Element 240 VAC 3kW

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3-Ton SpacePak chiller
Cooling (47°F water)
Ambient
Temp
Capacity Chiller
Power
Chiller
COP
Chiller
EER
Deg F BTU/hr Watts
82 38,553 2,523 4.47 15.28
95 29,694 3,873 2.25 7.67
105 22,880 4,912 1.36 4.66
Heating
Ambient
Temp
Water
Supply
Temp
Capacity Chiller
Power
Chiller
COP
Deg F Deg F BTU/hr Watts
45 115 35,536 3,855 2.70
32 110 26,295 3,472 2.22
20 105 20,245 3,103 1.91
5-Ton SpacePak chiller
Cooling (47°F water)
Ambient
Temp
Capacity Chiller
Power
Chiller
COP
Chiller
EER
Deg F BTU/hr Watts
82 61,526 5,150 3.50 11.95
95 54,621 5,881 2.72 9.29
105 45,668 6,643 2.01 6.87
Heating
Ambient
Temp
Water
Supply
Temp
Capacity Chiller
Power
Chiller
COP
Deg F Deg F BTU/hr Watts
45 115 60,256 6,919 2.55
32 110 42,770 5,927 2.11
20 105 24,769 4,125 1.76
Section 11: Performance data

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Section 12: LIMITED WARRANTY
Air to Water Heat Pump / Reverse Cycle Chiller
The “Manufacturer” warrants to the original owner at the original installation site that the Air to
Water Heat Pump / Reverse Cycle Chiller (the “Product”) will be free from defects in material or
workmanship for a period not to exceed one (1) year (parts) or two (2) years (compressor) from the
startup. If upon examination by the Manufacturer the Product is shown to have a defect in material
or workmanship during the warranty period, the Manufacturer will repair or replace, at its option, that
part of the Product which is shown to be defective.
This limited warranty does not apply:
a) if the Product has been subjected to misuse or neglect, has been accidentally or
intentionally damaged, has not been installed, maintained or operated in accordance
with the furnished written instructions, or has been altered or modified in any way.
b) to any expenses, including labor or material, incurred during removal or reinstallation of
the defective Product or parts thereof.
c) to any workmanship of the installer of the Product.
This limited warranty is conditional upon:
a) shipment, to the Manufacturer, of that part of the Product thought to be defective. Goods
can only be returned with prior written approval from the Manufacturer. All returns must
be freight prepaid.
b) determination, in the reasonable opinion of the Manufacturer, that there exists a defect
in material or workmanship.
Repair or replacement of any part under this Limited Warranty shall not extend the duration of the
warranty with respect to such repaired or replaced part beyond the stated warranty period.
THIS LIMITED WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EITHER EXPRESS OR
IMPLIED, AND ALL SUCH OTHER WARRANTIES, INCLUDING WITHOUT LIMITATION IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE
HEREBY DISCLAIMED AND EXCLUDED FROM THIS LIMITED WARRANTY. IN NO EVENT
SHALL THE MANUFACTURER BE LIABLE IN ANY WAY FOR ANY CONSEQUENTIAL, SPECIAL,
OR INCIDENTAL DAMAGES OF ANY NATURE WHATSOEVER, OR FOR ANY AMOUNTS IN
EXCESS OF THE SELLING PRICE OF THE PRODUCT OR ANY PARTS THEREOF FOUND TO
BE DEFECTIVE. THIS LIMITED WARRANTY GIVES THE ORIGINAL OWNER OF THE PRODUCT
SPECIFIC LEGAL RIGHTS. YOU MAY ALSO HAVE OTHER RIGHTS WHICH MAY VARY BY EACH
JURISDICTION.