Mitsubishi Heavy Industries FDT Series Technical Manual page 407

Error code
E42
Remote controller:
Outdoor control PCB
Outdoor inverter
1. Applicable model
All models
2. Error detection method
In order to prevent from
overcurrent of inverter,
if the current exceeds the
compressor stopping.
3. Condition of Error displayed
• If the output current of inveter
it makes the compressor
stopping.
• After 3-minute delay, the
compressor restarts, but if this
amonaly occurs 4 (3) times
within 30 (20) minute after the
intial detection.
Note (1) Value in ( ) is the model
SRC 40-60.
4. Presumable cause
• Defective inverter PCB
• Faulty power supply
• Insufficient refrigerant amount
• Faulty compressor
• Faulty power transistor
module
Note:
LED Green
Indoor Keeps flashing
Keeps flashing
Yellow LED
PCB
1 time flash
5. Troubleshooting
From previous page
Is the
checked result of power
transistor module
OK?
YES
• Is the space for installation of indoor and/or outdoor unit enough?
• Is there any short circuit of air on indoor and/or outdoor unit?
• At cooling, does the outdoor fan motor run?
Are the service valves fully opened?
Is the filter clogged?
• At heating, does the indoor fan motor run?
Are the service valves fully opened?
Is the filter clogged?
• Is there any liquid flooding?
Is the superheat within normal range?
Is the low pressure sensor and suction pipe temperature
thermistor normal?
• Is there any anoumalous sound on the compressor?
YES
After
resetting power for
several times does it
become normal?
YES
Temporary noise may cause of anomaly.
If noise source can be found, take countermeasure.
Red
Content
Stays OFF
1 time flash
Current cut (2/2)
Diagnosis
NO
NO
- 406 -
'12 • PAC-T-173
Countermeasure
Defective inverter PCB
Replace.
Defective inverter PCB
Replace.