Fujitsu AU*24LUAR Service Instruction page 72

Trouble shooting 13
OUTDOOR UNIT Error Method:
INDOOR UNIT
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 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)
HIGH PRESSURE SW
RED
1
CN37
RED
2
BLACK
1
2
BLACK
3
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.
Indicate or Display:
Indoor Unit
Outdoor Unit : LED 9 times blink/ 8 times blink(AU*24LMAKL)
ERROR CODE : E : 16
Detective details:
When pressure switch open is detected in 10 seconds
after the power is turned on.
4WV
: No LED
NO NO
07-16