Fujitsu AOU30RLXEH, Service Instruction

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Trouble shooting 19
OUTDOOR UNIT Error Method:
Compressor Thermistor Error
Compressor temperature thermistor
Detective Actuators: Detective details:
Indicate of Display:
Compressor Temp. Thermistor
Discharge Temp. Thermistor
BLACK
BLACK
1
2
3
4 1
2
3
4
CN62
BLACK
BLACK
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
292.91
-20
-4
531.56
70
158
8.70
168.60 100.91 62.55 40.01 26.34 17.79
60
140
12.30 Resistance value (k )
Temperature ( °C )
Temperature ( °F )
90 100 110 120
194 212 230 248
4.60
80
176
6.27
3.43 2.60 2.00
Resistance value (k )
1. Connector connection failure, open 2. Thermistor failure 3. Main PCB failure
Forecast of Cause:
Outdoor unit :
POWER
MODE
ERROR
2
7
(L1) (L2) (L6) (L5) (L4) (L3)
2
PUMP
DOWN
LOW
NOISE
PEAK
CUT
02-22
When Compressor temperature thermistor open or short-circuit is detected
at power ON or while running compressor.
Indoor Unit :
Operation lamp: 7 times Flash,
Timer lamp : 2 times Flash
ERROR CODE : [E : 72]
n: n times blinking : Light ON : Light OFF