Fujitsu AUXB04GALH Service Manual page 153

Trouble shooting 65
OUTDOOR UNIT Error Method:
Low Pressure Abnormal
Detective Actuators:
Suction pressure sensor
Forecast of Cause :
1. 3-way valve not opened
3. Outdoor unit fan operation defective, foreign matter at heat exchanger
4. EEV defective, strainer clogged
7. Low pressure sensor characteristics defective
<Cooling operation>
Check Point 1 : Check if 3-way valve is open.
If the 3-way valve was closed, open the
3-way valve and check operation.
OK
Check Point 4 : Check the indoor unit EEV, strainer clogging
Indoor unit EEV operation check
Strainer not clogged?
OK
Check Point 6 : Check the solenoid valve (SV1)
Solenoid valve operation check
Refer to "Service Parts Information 17".
OK
Check Point 7 : Check the suction pressure sensor
Suction pressure sensor characteristics check
* For the characteristics of the suction pressure sensor,
refer to "Service Parts Information 22".
OK
Check Point 8 : Check the refrigerant amount
Leak check
After fixing the problem and for canceling the Error, Error Reset (F3-40) will be required after power reset
Indicate or Display:
EA5. 1
Outdoor Unit : E. A 5. 1
Indoor Unit : Operation LED 9 times Flash, Timer LED 15 Times Flash,
Error Code : 9 U / A 6
Detective details:
"Protection stop by "suction pressure
or "suction pressure
was generated 5 times within 3 hours
2. Outdoor unit ambient temperature too low
5. Solenoid valve defective
04-77
Filter LED Continuous Flash.
15psi (0.10MPa)continued for 10 minutes"
7.25psi (0.05MPa)" during operation of any compressor""
<Heating operation>
Check Point 1 : Check if 3-way valve is open.
If the 3-way valve was closed, open the
3-way valve and check operation.
OK
Check Point 2 : Check the outdoor unit ambient temperature
Outdoor ambient temperature lower than operating range?
OK
Check Point 3 :
Check the outdoor unit fan operation, heat exchanger
No foreign matter in air passage?
Heat exchange fins clogged
Fan rotates?
Outdoor unit fan motor check
OK
Check Point 4 : Check the outdoor unit EEV, strainer clogging
Outdoor unit EEV1, EEV2 operation check
Strainer not clogged?
Refer to "Service Parts Information 14,15 ".
OK
Check Point 5 : Check the 4-way valve (4WV1, 4WV2, 4WV3)
4-way valve operation check.
Refer to "Service Parts Information 18".
6. 4-way valve defective
8. Insufficient refrigerant