Fujitsu ARU7RLF Service Instruction page 62

Trouble shooting 23
OUTDOOR UNIT Error Method:
INDOOR UNIT
High Pressure Switch Error
Detective Actuators:
Outdoor Unit Main PCB Circuit
Pressure Switch
Forecast of Cause :
1. Connector connection failure 2. Pressure Switch failure 3. Main PCB failure
Check Point 1 : Reset Power Supply and operate
Does abnormal LED indication show again?
YES
Check Point 2 : Check voltage of Main PCB (DC5.0V)
Check Point 3 :
Make sure circuit diagram of outdoor unit and check terminal voltage
at Pressure Switch. (DC5.0V)
RED
1
CN37
RED
2
WHITE
1
CN36 WHITE
2
If the voltage does not appear, replace Main PCB.
OK
Check Point 3 : Check Pressure Switch
Check if connector is loose or cable is open.
>> If no abnormal connection is found,
replace Pressure Switch.
After replacing Pressure Switch, check operating
condition and pressure in operation.
Characteristics of pressure switch
PRESSURE SWITCH 1 (CN37)
Contact : Short Open
Contact : Open Short
Indicate or Display:
Refer to error code table.
Detective details:
When pressure switch open is detected in 10 seconds
after the power is turned on.
PRESSURE SWITCH 1
PRESSURE SWITCH 2
Pressure switch 1
608.7 14.5 PSI
463.8 21.7 PSI
NO
PRESSURE SWITCH 2 (CN36)
Contact : Short Open
Contact : Open Short
02-27
Pressure switch 2
536.2 29.0 PSI
420.1 29. 0PSI