Fedders GWH18MC-D3DNA1A/O, Service Manual

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58
Troubleshooting
34 U3 □ ■ ■ ■
35 PL □ ■ ■ □
36 EU ■ ■ ■
☆
37 U7 ■ □
☆
□
38 U9 ■ ■
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39 FH ■ ■ ■ □
Cooling, dehumidifying;
compressor will stop,
indoor fan motor works.
Heating: all will stop
Cooling, dehumidifying;
compressor will stop,
indoor fan motor works.
Heating: all will stop
Overload normal works,
compressor running frequency
declines
This malfunction happened,only
in heating m o d e , all will
stop to run
Cooling: compressor
will stop, indoor fan
motor works.
Heating: all will stop
All loadsworknormally
but the running frequency
limited or decrease
Off 3s
blink
20 times
Off 3s
blink
21 times
Power voltage
is not staable
Replace the outdoor control board
AP1
Indoor unit air return is poor
or fan speed is too low
1.Power supply voltage is
lower than AC175V
2.Wire terminal 4V loosen
or wire break
3.4V damaged, replace 4V
Whole unit break for 20mins
and discharge,to check the
outdoor control board AP1’s
IPM module coolant whether
is short, the radiator is
tightened. If above phenomenon
is not ok, please improve or
replace the control board
AP1
1.Check the Input voltage if the
Voltageis lower than 150VAC, restart
the machine when the power supply
is normal
2.Checking the reactor L connection
Low DC Bus voltage
protection
IPM temp. is too
high limit/decrease
frequency
Four-way valve
abnormal
Outdoor unit zero-
cross
detecting error
Anti-freezing
limit/decrease
frequency
DC Bus voltage
dips
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