FCM4, FEV, FEM4, FJM, FMA4, FSA4, FSM4, FSU4, FVM4, FXM4, REM4, WAH, WAM, WAP, WAX, WBHL: Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
15
4. Check Plug 3, terminals 4 and 5, to ensure there are 240V.
5. Turn off power.
6. Reconnect Plug 3 to motor.
The following troubleshooting techniques will assist in determining the
correct component to replace when the Fan Coil Board presents a Fault
Code 44 or 41:
1. Disconnect power from the unit (240V).
2. Disconnect the DX+, DX-, C, R connector from the board.
3. Disconnect Plug 1 from the board (Fig. 10).
4. Turn on power (240V).
5. After reestablishing power, you should receive Fault Code 44, and
the motor LED should be off.
6. Place a jumper across the R and G terminals on the low voltage
terminal block.
7. Fault Code 44 should still be flashing.
8. The Motor LED should be flashing, indicating the board is able to
transmit a signal to the motor.
9. If Motor LED is not flashing, check to ensure that 24V is present
across R and C on the low voltage terminal block and that there is a
good connection with the R and G jumper.
10. If 24V is present and the jumper/connections are good,
11. Replace the board.
Check Board
1. If Fault Code 44 and the Motor LED are both flashing, place a DC
voltmeter across terminals PL1-1 Red (+) to PL1-2 Green (-)
(Fig. 10).
2. Across terminal PL1-1 and PL1-2, a 12VDC should be present. If
12VDC is not present, replace circuit board.
3. If Fault Code 44 is flashing and the Motor LED is flashing, place a
DC voltmeter across terminal PL1-3 (+) and PL1-2 (-).
4. Across terminal PL1-3 (+) and PL1-2 (-), the DC volt meter should
display 5VDC. The voltage should be very stable and should not
fluctuate more than 0.02VDC. If the voltage fluctuates, get a
different voltmeter before proceeding to the following steps.
5. Reconnect Plug 1 to circuit board and connect DC voltmeter across
terminals PL1-3 Yellow (+) and PL1-2 Green (-). Does the voltage
appear to fluctuate more than in step 15? Typical voltmeters will
show a fluctuation of 2VDC to 1VDC. The amount of fluctuation is
not important. You could see even more fluctuation depending on
the voltmeter used.
A13030
Fig. 9 – FCM4 Circuit Board LED Locations
A13031
Fig. 10 – ECM/Plug Wiring Diagram
6. Check the blower motor serial output signal. The blinking LED on
the control board represents the serial output signal. You can
measure the signal with a DC voltmeter by removing Plug 1 from
the circuit board and connecting the DC voltmeter across PL1-4 (+)
and PL1-2 (-). The voltage should be near 0Vdc but it will fluctuate
briefly several times per second. If you have an analog voltmeter,
the needle briefly will go high several times per second. If you have
a digital voltmeter with a bar graph, it will show a large change in
magnitude on the bar graph several times per second. If you have a
plain, digital voltmeter, it will show a brief fluctuation in voltage,
and the magnitude may vary depending on the voltmeter used.
FMA4P, WAMA, FMA4X, WAXA
FAN MOTOR
FMA4P, WAMA
The FMA4P and WAMA motor is three-speed ECM 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 24VAC 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 24VAC 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 not run, test motor for an open winding or a winding
shorted to motor case. If either is present, replace motor.
FMA4X, WAXA
The FMA4X and WAXA motor is five-speed direct drive. The cooling
speed tap is selected by connecting the green wire to the desired motor
tap number indicated on the motor plug. For the electric heat fan speed
selection connect the white wire to the desired motor tap number
indicated on the motor plug.
Status
LED
Communication
LED
Motor
LED
WARNING
!
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.
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