Fujitsu Inverter Halcyon AOU12RL, Service Instruction

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Trouble shooting 4
INDOOR UNIT
INDOOR UNIT Error Method:
Indicate or Display:
Outdoor Unit : No indication
Indoor Unit : Operation LED : 2 times, Timer LED : 3 times
ERROR CODE : [E : 04]
Detective Actuators:
Detective details:
Forecast of Cause :
Check Point 2 :
31.7 39.6 49.7 62.9 80.3 103 134 176 Resistance Value (k )
Temperature
OK OK
OK
17.1 20.8 25.6 Resistance Value (k )
Temperature
Indoor Heat Exchanger Temperature
Sensor Error
Indoor Unit Controller PCB Circuit
Heat Exchanger Temperature Thermistor
When Heat Exchanger Temperature Thermistor open or short-circuit is
detected at power ON.
1. Connector connection failure 2.Thermistor failure 3. Controller PCB failure
Check Point 1 : Check connection of Connector
Check if connector is removed.
Check erroneous connection.
Check if thermistor cable is open.
>>Upon correcting the removed connector or mis-wiring, reset the power.
Check Point 2 : Remove connector and check Thermistor resistance value
Thermistor Characteristics (Approx. value)
If Thermistor is either open or shorted, replace it and reset the power.
Check Point 3 : Check voltage of Controller PCB (DC5.0V)
Make sure circuit diagram of indoor unit and check terminal voltage at Thermistor (DC5.0V)
If the voltage does not appear, replace Controller PCB.
06-08
THERMISTOR
(PIPE TEMP.)
THERMISTOR
(ROOM TEMP.)
BLACK BLACK BLACK BLACK
CN4
1 2 3 4
1 2 3 4
95 °F
(35 °C)
86 °F
( 30 °C)
77 °F
( 25 °C)
68 °F
(20 °C)
59 °F
(15 °C)
50 °F
(10 °C)
41 °F
(5 °C)
32 °F
(0 °C)
122 °F
( 50 °C)
113 °F
(45 °C)
104 °F
( 40 °C)