Fujitsu AUXG30KRLB, Service Instruction

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Detective Actuators:
Indoor unit Controller PCB Circuit
Indoor Temperature Thermistor
Detective details:
Indoor unit thermistor is open or short is detected always.
Forecast of Cause :
1. Connector failure connection 2. Thermistor failure 3. Controller PCB failure
Check Point 2 : Remove connector and check Thermistor resistance value
Thermistor Characteristics(Rough value)
If Thermistor is either open or shorted, replace it and reset the power.
Check Point 1 : Check connection of Connector
Check if connector is loose or removed
Check erroneous connection
Check if thermistor cable is open
>>Reset Power when reinstalling due to removed connector or incorrect wiring.
OK
OK
Check Point 3 : Check Voltage of Controller PCB (DC 5.0V)
Make sure circuit diagram of each indoor unit and check terminal voltage at Thermistor (DC5.0V)
If the voltage does not appear, replace Controller PCB and execute the check operation again.
Trouble shooting 14
INDOOR UNIT Error Method:
Indoor Room Thermistor Error
Indicate or Display:
02-15
DC
Error code : 41
Outdoor unit :
n: n times blinking : Light ON : Light OFF
Mode Error L1 L2 L6 L5 L4 L3
2 5 15
1
2
3
1
2
3
CN8
H/E Thermistor
Room Temp. Thermistor
RED
RED
BLACK
BLACK
1
2
1
2
CN32
Resistance value (k )
Temperature (°C )
Temperature (°C ) -10 -5 0 5 10 15 20 25
30 35 40 45
Resistance value (k )
58.2 44.0 33.6 25.9 20.2 15.8 12.5 10.0
8.0 6.5 5.3 4.3