Fujitsu AOU30RLXEH, Service Instruction

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1. Connector failure connection 2. Thermistor failure 3. Controller PCB failure
Test 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.
Test 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
Test 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.
Temperature ( °C )
Temperature ( °F )
-10 0 10 20 30 40 50
14 32 50 68 86 104 122
312.27
-30
-22
1131.91
-20
-4
579.59
60
140
11.64
65
149
9.69
176.03 103.34 62.91 39.57 25.64 17.06
Resistance value (k )
Temperature ( °C )
Temperature ( °F )
Resistance value (k )
Room Temp. Thermistor
Pipe Temp. Thermistor
BLACK
BLACK
1
2
3
4 1
2
3
4
CN1
BLACK
BLACK
Trouble shooting 12
INDOOR UNIT Error Method:
Indoor Heat Ex. Thermistor Error
Indoor unit controller PCB circuit
Heat exchanger thermistor
Heat exchanger temperature thermistor is open or short is detected always.
Detective Actuators: Detective details:
Indicate of Display:
Forecast of Cause:
02-15
n: n times blinking
: Light ON : Light OFF
Outdoor unit :
POWER
MODE
ERROR
2
5
(L1) (L2) (L6) (L5) (L4) (L3)
15
PUMP
DOWN
LOW
NOISE
PEAK
CUT
Indoor Unit :
Operation lamp: 4 times Flash,
Timer lamp : 2 times Flash
ERROR CODE : [E : 42]