Tempstar FPMN Series Installation and user guide

1
FPM(A,B)N(C,U)
FMC4X, FMC4Z,
FMU4X, FMU4Z
Service and Maintenance Instructions
Horizontal Fan Coil Units
NOTE: Read the entire instruction manual before starting the
installation.
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS 1..............................
INTRODUCTION 1.......................................
FAN COIL DESCRIPTION AND TROUBLESHOOTING 2........
MULTI−SPEED ECM FAN MOTOR 2.........................
FAN SPEED SELECTION 2.................................
FAN MOTOR 2...........................................
ELECTRIC HEATER SERVICE 2.............................
CLEANING OR REPLACING
REFRIGERANT FLOW−CONTROL DEVICE 2.................
SEQUENCE OF OPERATION 2..............................
ELECTRIC HEATER FUNCTION
AND TROUBLESHOOTING 3..............................
CARE AND MAINTENANCE 6.............................
Air Filter 6...........................................
Cooling Coil, Drain Pan, and Condensate Drain 6.............
Disconnecting the Control Box Assembly 7..................
FPM(A,B)N, FMC4X, FMU4X
Disconnecting the Blower Assembly 7......................
FPM(A,B)N, FMC4X, FMU4X
Servicing the Fan Motor 8...............................
FMC4Z & FMU4Z
Disconnecting the Blower Assembly 9......................
FMC4Z & FMU4Z
Servicing the Fan Motor 11..............................
Cleaning the A−Coil 12.................................
Removing the Drain Pan 12..............................
Changing the A−Coil 12.................................
Refrigerant Metering Device 13...........................
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory−authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing
and work gloves. Have a fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions
included in literature and attached to the unit. Consult local
building codes and the current editions of the National Electrical
Code (NEC) NFPA 70.
In Canada, refer to the current editions of the Canadian Electrical
Code CSA C22.1.
Recognize safety information. This is the safety−alert symbol .
When you see this symbol on the unit and in instruction manuals,
be alert to the potential for personal injury.
Understand the signal words DANGER, WARNING, and
CAUTION. These words are used with the safety−alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies hazards
which could result in personal injury or death. CAUTION is used
to identify unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or
operation.
UNIT OPERATION AND SAFERTY HAZARD
Failure to follow this warning could result in personal injury
or death.
Puron (R−410A) systems operate at higher pressures than
R−22 systems. Do not use R−22 service equipment or
components on R−410 equipment. Ensure service equipment
is rated for R−410.
!WARNING
INTRODUCTION
FPM(A,B)N(C,U), FMC4X, FMC4Z, FMU4X, FMU4Z Fan Coils
are designed for horizontal orientation and are suitable for ceiling
installations. The FPM(A,B)NC, FMC4X, FMC4Z models are
cased and configured from the factory for bottom return
applications. FPM(A,B)NU, FMU4X, FMU4Z models are
uncased. All units are available with field−installed electric heat.
Units are used indoors as the fan coil for split−system heat pumps
or air conditioners.
FPMAN(C,U) units are factory−equipped with a piston refrigerant
metering device and are available in 18,000 through 36,000 Btuh
nominal cooling capacities. FPMBN(C,U), FMC4X, FMU4X,
FMC4Z, FMU4Z are factory−equipped with a TXV refrigerant
metering device and are available in 18,000 through 30,000 Btuh
nominal cooling capacities.
The coil is equipped with sweat−type connections and is
vapor−charged with dry nitrogen.
Units are designed for horizontal applications only. Local codes
may limit this free−air−return type unit to installation in
single−level applications.

2
FAN COIL DESCRIPTION
AND TROUBLESHOOTING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installation or servicing system, always turn off main
power to system. There may be more than one disconnect
switch. Turn off accessory heater power if applicable. Lock out
and tag switch with a suitable warning label.
!WARNING
MULTI−SPEED ECM FAN MOTOR
The multi−speed ECM motor used with this product contains two
parts: the control module and the motor winding section.
A. It is normal for the motor to rock back and forth on startup. Do
not replace the motor if this is the only problem identified.
B. If the motor is not running:
1. Check for proper high voltage and ground at the L,G, and N
connections at the motor. Correct any voltage issue before
proceeding to the next step.
2. The motor is communicated through 24−Vac signals to the
1, 2, 3, 4, 5 and C (common) terminals. Verify the part
number of the motor matches the correct replacement motor
part number for the unit model number.
3. Initiate a demand from the thermostat and check the voltage
between C (common) and terminal 1 −5. If voltage is
present and the motor isn’t operating, then the motor/control
module is failed.
Fan Speed Selection
The fan speed selection is done at the motor connector. Units with
or without electric heaters require a minimum CFM. Refer to the
unit wiring label to ensure that the fan speed selected is not lower
than the minimum fan speed indicated.
Table 1 – FMC4Z & FMU4Z ECM Motor Speed Taps
Tap
Delay−
off
Time(s) 18 24 30 36
Tap 1 90 Default
Tap 2 90 Default
Tap 3 90 Default
Tap 4 90 Default
Tap 5 90
FAN MOTOR
The motor is three−speed direct drive. High−speed lead is black,
medium−speed lead is red, low−speed lead is blue, and common
lead is purple. Be sure proper blower speed has been selected.
The motor is turned on through two different routes. The first
occurs when thermostat calls for the fan in cooling, heat pump, or
fan−only mode. A 24−Vac signal is sent to relay, causing relay to
close its normally open contacts, turning fan on.
The second occurs when there is a call for electric heat. A 24−Va c
signal is sent to heater sequencer/relay, causing it to close, directing
230V through the normally closed contact of fan relay, turning fan
on. The fan remains on until sequencer/relay opens.
If motor does run, test motor for an open winding or a winding
shorted to motor case. If either is present, replace motor.
ELECTRIC HEATER SERVICE
Service can be completed with heater in place. Shut off power
before servicing.
A. Limit Switch
Refer to Electric Heater Kit Function and Troubleshooting section
of this manual.
B. Relay
Refer to Electric Heater Kit Function and Troubleshooting section
of this manual.
C. Transformer
A 40−VA transformer supplies 24−V power for control circuit.
Check for 208/230V on primary side of transformer. If present,
check for 24V on secondary side.
NOTE: Transformer is fused. Do not short circuit.
D. Fan Relay
Relay coil is 24−V. Check for proper control voltage. Replace relay
if faulty.
CLEANING OR REPLACING REFRIGERANT
FLOW−CONTROL DEVICE
The FPMAN(C,U) piston can be removed and cleaned if believed
to be plugged. This unit’s piston is unique and replacements are
available from RCD.
The filter drier should be located on the liquid line at the indoor
unit to prevent particulate from plugging the piston.
SEQUENCE OF OPERATION
A. Condensing Unit
COOLING
When thermostat calls for cooling, the circuit between R and G is
complete and FR is energized. The normally open contacts close
causing blower to operate.
The circuit between R and Y is also complete. This completed
circuit causes contactor in outdoor unit to close which starts
compressor and outdoor fan.
HEATING
When thermostat calls for heating and FAN switch is set on AUTO,
the circuit between R and W is complete. The heater relay is
energized which closes contacts of relay. This completed circuit
energizes all heating elements HTR and blower motor.
B. Heat Pump
COOLING
On a call for cooling, the thermostat makes circuits R−O, R−Y, and
R−G. Circuit R−O energizes reversing valve, switching it to
cooling position. Circuit R−Y energizes contactor starting outdoor
fan motor and compressor. Circuit R−G energizes indoor unit
blower relay starting indoor blower motor.
When thermostat is satisfied, its contacts open de−energizing
contactor reversing valve and blower relay. This stops compressor
and fan motors.
HEATING
On a call for heating, the thermostat makes circuits R−Y and R−G.
Circuit R−Y energizes contactor starting outdoor fan motor and
compressor. Circuit R−G energizes indoor blower relay starting
blower motor.
Should temperature continue to fall, R−W circuit is made through
second−stage room thermostat bulb. Circuit R−W energizes a relay
bringing on supplemental electric heat.
Circuit R−W also energizes the compressor lockout relay which
breaks the R−Y circuit. This prevents the simultaneous operation of
the heat pump and electric heater.
When thermostat is satisfied, its contacts open, de−energizing
contactor and relay. All heaters and motors should stop.

3
ELECTRIC HEATER FUNCTION AND
TROUBLESHOOTING
This section describes EHK3 series electric heaters by examining
functional operation of this heater.
Service can be completed with heater in place. Shut off power
before servicing.
DESCRIPTION OF ELECTRIC HEATER COMPONENTS
A. Limit Switch
The limit switch is a temperature sensitive control that’s function is
to prevent system from overheating in abnormal conditions. The
temperature settings often vary from heater to heater due to
variations in airflow patterns and element radiant heat conditions.
The devices are sized to remain on-line under heat pump
conditions (115_F air off coil) and minimum CFM, but trip to
prevent outlet air conditions above 200_F or excessive component
or duct temperatures. The device itself consists of a bimetallic disc,
which when overheated “snaps through” to open a normally closed
high-voltage, high-current switch. When system temperatures cool
sufficiently, the switch will automatically reset to its closed
position. Normal failure mode for this switch is open.
If a limit switch has been determined to be defective, NEVER
BYPASS THE LIMIT SWITCH. When replacing limit switch,
ensure that it is replaced with a limit switch of identical opening
temperature and closing differential. Limits switches are typically
color−coded to identify their range.
B. Relay
The relays used on these heat kits utilize rectifier boards that sit
atop the double pole relays. The rectifier board converts the 24AC
signal into a DC current to drive relay. This heater control system
does not incorporate any time delays. The fan motor is
interconnected to one of the heater elements, this ensures fan
operation during heater operation.
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
BLOWER PARTS
DUCT COMPONENTS
WRAPPER ASSY
EVAPORATOR PARTS
ELECTRICAL PARTS
0.8315
A180050
Fig. 1 −Expanded Parts

4
2 Blower Motor 10 Capacitor
9 Capacitor Strap
1 Blower Assy(2 pieces)
3 Motor Axle Support Right
4 Motor Holder
5 Motor Axle Support Left
6 Motor Mount
7 Blower Support Plate
8 Capacitor Cover
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
A180030
Fig. 2 −PSC Blower Parts
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
1 Control Mounting Plate
3 Time Delay Relay 4 Blower Relay
5 Terminal Block
2 24v Transformer
6 Ground Lug
8 Motor Cover
7 Control Box Cover
9 Heater BlankO Plate
A180027
Fig. 3 −PSC Electrical Parts

5
1 Top Panel Assy
5 Condensate bae Assy
6 Drain pan
2 Insulation Foam
3 Insulation Bracket Ċ
4 Insulation Bracket ĉ
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
A180028
Fig. 4 −Internal Case
4 Header Assy
1 Coil (2 pieces)
2 Coil Support Plate(Right Side)
3 Coil Air Diverter
7 Capillary I
6 Capillary II
5 Distributor
9 Throttle
8 Coil Support Plate(Left Side)
(Piston Installed)
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
A180029
Fig. 5 −Coil Parts

6
NOTE: This illustration is for reference only. Unit may differ in appearance or may not include all components shown.
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A180051
Fig. 6 −FMU4Z and FMC4Z Models −Blower and Coil Parts
CARE AND MAINTENANCE
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect and clean or replace air filter each month or as re-
quired.
2. Inspect cooling coil, drain pan, and condensate drain each
cooling season for cleanliness. Clean as necessary.
3. Inspect blower motor and wheel for cleanliness each heating
and cooling season. Clean as necessary.
4. Inspect electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
as necessary.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing and gloves when handling
parts.
CAUTION
!
A. Air Filter
The air filter should be replaced as needed.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Never operate unit without a filter.
CAUTION
!
B. Cooling Coil, Drain Pan, and Condensate Drain
The cooling coil is easily cleaned when it is dry. Inspect coil and
clean (if necessary) before each cooling season. To check or clean
cooling coil, remove blower/heater access panel to gain full access
to cooling coil. If coil is coated with dirt or lint, vacuum with a soft
brush attachment.
Be careful not to bend coil fins. If coil is coated with oil or grease,
clean it with a mild detergent and water solution. Rinse coil with
clear water.
Be careful not to splash water onto insulation.
Inspect drain pan and condensate drain at same time cooling coil is
checked. Clean drain pan and condensate drain by removing any
foreign matter from pan. Flush pan and drain tube with clear water.
If drain tube is restricted, it can generally be cleared by
high−pressure water. Cut plastic line and work outside condensate
pan and away from coil to clear drain tube.
NOTE: There MUST be a trap in condensate line. Trap must be at
least 3−in. deep, not higher than the bottom of unit condensate
drain opening, and pitched downward to an open drain or sump.

7
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Do not use caustic household drain cleaners in the condensate
pan or near the coil. Drain cleaners can quickly destroy a coil.
CAUTION
!
C. Disconnecting the Control Box Assembly
1. Disconnect power.
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installation or servicing system, always turn off main
power to system. There may be more than one disconnect
switch. Turn off accessory heater power if applicable. Lock out
and tag switch with a suitable warning label.
!WARNING
2. Remove control box cover (four screws).
A13385
Fig. 7 −Control Box Cover Removal
3. Remove control box assembly (five screws). If there is not
enough slack in field wiring (high and low voltage), it is
recommended to disconnect field wiring.
A13386
Fig. 8 −Control Box Removal
D. FPM(A,B)N, FMC4X, FMU4X −Disconnecting the Blower
Assembly
1. Disconnect power.
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installation or servicing system, always turn off main
power to system. There may be more than one disconnect
switch. Turn off accessory heater power if applicable. Lock out
and tag switch with a suitable warning label.
!WARNING
2. Remove control box cover (four screws). (See Fig. 7.)
3. Disconnect the (four) blower−motor power wires, noting
connection locations. (See Fig. 8.)
4. Loosen the conduit holding ties.
A13387
Fig. 9 −Conduit Holding Ties
5. Remove the four outer screws that attach the blower support
plate to each evaporator coil support.

8
A13388
Fig. 10 −Blower Support Plate Screws
6. Remove the two middle screws above/behind the blower
motor that’s attached to the top plate.
PERSONAL INJURY HAZARD
Failure to follow this caution may result in personal injury.
After removing the sixth and final screw in Step 6, the blower
assembly will be completely disconnected from the unit. Be
ready to lower the blower assembly.
CAUTION
!
A13389
Fig. 11 −Remove Middle Screws
E. FPM(A,B)N, FMC4X, FMU4X −Servicing the Fan Motor
1. After removing the blower housing from the unit, discon-
nect ground wire from screw on grounding bracket.
A13390
Fig. 12 −Disconnect Ground Wire
2. Remove grounding bracket from motor−mount assembly.
At this point, the clamp brackets will be loose and can be
removed.
A13391
Fig. 13 −Remove Grounding Bracket
3. Remove capacitor cover.
A13392
Fig. 14 −Capacitor Cover

9
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in equipment
damage or equipment damage.
Capacitors can store electrical energy when power is off.
Electrical shock can result if you touch the capacitor terminals
and discharge the stored energy. Exercise extreme caution
when working near capacitors. With power off, discharge
stored energy by shorting across the capacitor terminals with a
15,000−ohm, 2−watt resistor.
Always check capacitors with power off. Attempting to
troubleshoot a capacitor with power on can be dangerous.
Defective capacitors may explode when power is applied.
Insulating fluid inside is combustible and may ignite, causing
burns.
!WARNING
4. Disconnect capacitor leads from capacitor.
A13393
Fig. 15 −Capacitor Leads
5. Loosen blower−wheel set screws from each motor shaft, ac-
cessing them through the blades of the blower wheels, with
a Phillips screwdriver.
A13394
Fig. 16 −Loosen Blower Set Screw
6. Disconnect one of the blower housings by removing the
four housing screws.
A13395
Fig. 17 −Disconnect Blower Housing
7. Remove housing from support plate and motor shaft.
A13396
Fig. 18 −Remove Blower Housing
8. Pull motor out of second housing, which can remain at-
tached to the support plate.
A13397
Fig. 19 −Remove Motor from Second Housing
9. Reverse these steps to reinstall.
F. FMC4Z & FMU4Z −Disconnecting the Blower Assembly
1. Disconnect power.
2. Remove control box cover (four screws). (See Fig. 20)

10
A180031
Fig. 20 −Removing Control Box Cover
3. Disconnect the blower motor white power plug and green
and wire speed tap wires, noting connection locations. (See
Fig. 21)
A180032
Fig. 21 −Disconnect the Blower Motor
4. Loosen the conduit holding ties. (See Fig. 22)
A180033
Fig. 22 −Loosen the Conduit Ties
5. Remove the two middle screws above/behind the blower
motor that’s attached to the top plate.
6. Remove the two outer screws that attach the blower support
plate to right evaporator coil support. (See Fig. 23)
A180034
Fig. 23 −Remove Outer Screws from Support Plate
7. Remove the top and middle screw of the refrigerant tubing
holding bracket. (See Fig. 24)
A180035
Fig. 24 −Remove Top and Middle Screw
8. Bend the holding bracket to release from around the tubing.
(See Fig. 25 & 26)
A180036
Fig. 25 −Remove Two Outer Screws

11
A180037
Fig. 26 −Screws Holding Support Plate
9. Remove the two outer screws that attach the blower support
plate to left evaporator coil support. (See Fig. 27) This will
completely release the blower assembly from the unit.
A180038
Fig. 27 −Two Outer Screws
PERSONAL INJURY HAZARD
Failure to follow this caution may result in personal
injury.
After removing the final screw from Step 9., the blower
assembly will be completely disconnected from the unit.
Be ready to lower the blower assembly.
CAUTION
!
G. FMC4Z & FMU4Z −Servicing the Fan Motor
1. After removing the blower housing from the unit, remove
grounding bracket from motor−mount assembly by remov-
ing the two screws. (See Fig. 28 & 29)
A180045
Fig. 28 −Screws Holding the Bracket
A180046
Fig. 29 −Bend the Holding Bracket
2. At this point, the clamp brackets will be loose and can be
removed. (See Fig. 30)
A180047
Fig. 30 −Remove Clamp Brackets

12
3. Loosen blower−wheel set screws from each motor shaft, ac-
cessing them through the blades of the blower wheels, with
a Phillips screwdriver. (See Fig. 16)
4. Disconnect one of the blower housings by removing the
four housing screws. (See Fig. 17)
5. Remove housing from support plate and motor shaft.
6. Pull motor out of second housing, which can remain at-
tached to the support plate.
7. The ECM module is attached below the motor with two
Philips head screws to a bracket. (See Fig. 31 & 32)
A180048
Fig. 31 −Remove Module
A180049
Fig. 32 −Remove Module
8. Reverse these steps to reinstall.
H. Cleaning the A−Coil
The A−coil can be accessed for cleaning by removing either the
control box assembly or the blower assembly. (Refer to those
previous instructions.)
I. Removing the Drain Pan
1. Disconnect condensate drains, if necessary.
2. Remove the four screws located near the corners.
(See Fig. 33)
3. Lower drain pan from unit.
A13398
Fig. 33 −Removing Condensate Pan
J. Changing the A−Coil
1. Disconnect power.
2. Disconnect field wiring (low and high voltage).
3. Disconnect condensate drain.
4. Remove entire fan coil unit from installation location.
5. Remove control box assembly. (See previous instructions.)
6. Remove blower assembly (See previous instructions.)
7. Remove drain pan (see previous) to the top plate.
8. From top of unit, remove the ten screws holding the coil
assembly to the top plate.
A13399
Fig. 34 −Remove Top−Plate Screws
9. Remove the top plate and insulation.

13
A13400
Fig. 35 −Top Plate and Insulation
10. Remove the two insulation support brackets.
A13401
Fig. 36 −Insulation Support Brackets
11. On bottom of unit, remove the eight screws attaching the
condensate baffle assembly to the side coil supports.
A13402
Fig. 37 −Condensate Baffle Screws
12. Remove condensate baffle assembly.
A13403
Fig. 38 −Remove Condensate Baffle Assembly
K. Refrigerant Metering Device
The refrigerant metering device is located on the side of the fan coil
unit, in−line with the liquid refrigerant line .
FPMAN(C,U) Fan coils are shipped with a piston metering device
designed for the most common outdoor unit matches. The piston
included with the fan coil is unique to this product and cannot be
replaced with the piston shipped with the outdoor unit. Refer to
AHRI ratings to check if your combination can use the piston
shipped with the unit or requires an accessory TXV.
FPMBN(C,U), FMC4X, FMU4X, FMC4Z, FMU4Z Fan Coils are
shipped with a TXV metering device.
Use two wrenches to remove the nut from the piston body or to
remove the TXV.
A13404
Fig. 39 −Metering Device Location / Piston (FPMA Units)

14
Copyright 2018 CAC / BDP D7310 W. Morris St. DIndianapolis, IN 46231 Edition Date: 03/18
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Catalog No: SM-FPMA-03
Replaces: SS-FPMA-02