Carrier 38GRQB12-3 Service Manual page 21

Dual-8
Malfunction Operation
No. Code
Name Indicator
Display
35 IPM protection H5
Module
36 temperature is H5
too high
Internal motor
37 (fan motor) do H6
not operate
Desynchronizing
38 H7
of compressor
39 PFC protection HC
Outdoor DC fan
40 motor L3
malfunction
41 power protection L9
Indoor unit and
42 outdoor unit LP
does not match
43 Failure start- up LC
Malfunction of
44 voltage dropping U1
for DC bus-bar
Malfunction of
45 voltage dropping U3
for DC bus-bar
Malfunction of
46 complete units U5
current detection
The four-way
47 valve is U7
abnormal
Zero-crossing
48 malfunction of U9
outdoor unit
Frequency
49
limiting (power)
Compressor
50
running
The temperature
for turning
51
on the unit is
reached
Frequency
52 limiting (module
temperature)
Normal
53
communication
OFF 3S
and blink
once
(during
54 Defrosting
blinking,
ON 10s
and OFF
0.5s)
Cool Heating Yellow Red
Indicator Indicator Indicator Indicator
OFF 1S
and blink
4 times
OFF 1S
and blink
10 times
OFF 1S
and blink
14 times
OFF 1S
and blink
14 times
OFF 1S
and blink
9 times
OFF 1S
and blink
16 times
OFF 1S
and blink
13 times
OFF 1S
and blink
once
OFF 1S
and blink
8 times
OFF 1S
and blink
11 times
Green
AC Status
Indicator
During cooling and drying
operation, compressor stops
while indoor fan operate.
During heating operation, the
unit stops operation.
Internal fan motor, external fan
motor, compressor and
electric heater stop operation,
guide louver stops at present
location.
During cooling and drying
operation, compressor stops
while indoor fan operates.
During heating operation, the
complete unit stops operation.
During cooling and drying
operation, compressor stops
while indoor fan operates.
During heating operation, the
unit stops operation.
Outdoor DC fan motor
malfunction lead to
compressor stop operation.
Compressor stops operation
and Outdoor fan motor stops
30s later, 3 minutes later fan
motor and compressor restarts
Compressor and Outdoor fan
motor can not work
During cooling and drying
operation, compressor stops
while indoor fan operates.
During heating operation, the
unit stops operation.
During cooling and drying
operation, compressor stops
while indoor fan operates.
During heating operation, the
unit stops.
During cooling and drying
operation, compressor stops
while indoor fan operates.
During heating operation, the
unit stops.
During cooling and drying
operation, compressor stops
while indoor fan operates;
during heating operating, the
unit stops operation.
If this malfunction occurs
during heating operation, the
unit will stop operation.
During cooling operation,
compressor stops while indoor
fan operates; during heating,
the complete unit stops
operation.
OFF 0.5S
and blink
once
Defrosting occurs in heating
mode. Compressor operates
while indoor fan stops
operation.
21
Possible Causes
Refer to the malfunction analysis
(IPM protection, loss of
synchronism protection and
over-current protection of phase
current for compressor
1. Bad contact of DC motor
feedback terminal.
2. Bad contact of DC motor control
end.
3. Fan motor is stalling.
4. Motor malfunction.
5. Malfunction of mainboard rev
detecting circuit.
Refer to the malfunction analysis
(IPM protection, loss of
synchronism protection and
over-current protection of phase
current for compressor.
Refer to the malfunction analysis
DC fan motor malfunction or
system blocked or the connector
loosened.
To protect the electronic
components when detect high
power
Indoor unit and outdoor unit does
not match
Refer to the malfunction analysis
Replace outdoor control panel AP1
Supply voltage is unstable
There is a circuit malfunction on
outdoor units control panel AP1,
replace the outdoor units control
panel AP1.
1.Supply voltage is lower than
AC175V;
2.Wiring terminal to the four way
valve is loose or broken;
3.four way valve is damaged,
replace four way valve.
Replace outdoor control panel AP1
It is the normal state