Fujitsu ASU18RMLQ Service Instruction page 64

Trouble shooting 33
OUTDOOR UNIT Error Method:
INDOOR UNIT
Compressor temperature error
Detective Actuators:
Outdoor Unit Main PCB Circuit
Compressor Temperature Thermistor
Forecast of Cause :
1. Valve is close 2. EEV failure
5. Outdoor Fan Operation failure 6. Outdoor Heat Exchanger clogged
< Cooling mode >
Check Point 1 : Check if Gas Valve is open
If it is not open, open it and check the operation.
OK
Check Point 2 : Check EEV and Strainer
Are EEV and Strainer open?
(Refer to PARTS INFORMATION 4)
>>If EEV or Strainer is defective, replace it.
OK
Check Point 3 : Check if gas leak or less gas
Measure Gas pressure, if there is a leak, correct it.
>>If recharging refrigerant, make sure to perform
vacuuming and
recharge the specified amount.
OK
Check Point 4 : Check Compressor Thermistor
Isn't it fallen off the holder?
Is there a cable pinched?
>> Check characteristics of thermistor (Refer to Trouble shooting 12),
If defective, replace the thermistor
OK
Check Point 5 : Check Outdoor FAN, Heat Exchanger
Is there anything obstructing the air distribution circuit?
Is there any clogging of Outdoor Heat Exchanger?
Is the Fan rotating? (Check by hand and if it is locked, replace the motor)
Check Outdoor Fan Motor.
>>If the Fan Motor is defective, replace it.
Indicate or Display:
Refer to error code table.
Detective details:
When the compressor temperature becomes higher than 125°C,
the compressor stops.
3. Gas Leak, less 4. Compressor Thermistor failure
< Heating mode >
MPa MPa
02-38
Check Point 1 : Check if LIquid Valve is open
If it is not open, open it and check the operation.
OK
Check Point 2 : Check EEV and Strainer
Are EEV and Strainer open?
(Refer to PARTS INFORMATION 4)
>>If EEV or Strainer is defective, replace it.
OK