Outdoor Heat Exchanger Temperature Sensor(Outlet) Error - Fujitsu AB A30LBT Series Service Instruction

Trouble shooting 5
OUTDOOR UNIT Error Method:
Outdoor Heat Exchanger Temperature
Sensor (Outlet) Error
Detective Actuators:
Outdoor Unit Main PCB Circuit
Heat Exchanger Temperature
Thermistor (Outlet)
Forecast of Cause:
1. Connector connection failure 2.Thermistor failure 3. Main 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.
OK
Check Point 2 : Remove connector and check Thermistor resistance value
Thermistor Characteristics (Approx. value)
Temperature (°C )
Resistance Value (k )
Temperature (°C )
Resistance Value (k )
If Thermistor is either open or shorted, replace it and reset the power.
OK
Check Point 3 : Check voltage of Main PCB (DC5.0V)
Make sure circuit diagram of outdoor unit and check terminal voltage at Thermistor (DC5.0V)
BROWN
1 1
CN 64 2 2
BROWN
3 3
BLUE
1 1
CN 62
2 2
BLUE
3 3
BROWN
1 1
CN 63
2 2
BROWN
3 3
BLACK
1 1
CN 65 2 2
BLACK
3 3
If the voltage does not appear, replace Main PCB.
Indicate or Display:
Refer to error code table.
Detective details:
When Heat Exchanger Temperature Thermistor (Outlet) open or
short-circuit is detected at power ON or while running the compressor.
-10 -5 0
27.8 21.0 16.1
35 40 45
3.11 2.53 2.08
THERMISTOR
( COMPRESSOR TEMP. )
THERMISTOR
( OUTDOOR TEMP. )
THERMISTOR
( DISCHARGE PIPE )
THERMISTOR
( HEAT EXCHANGER )
02-09
5 10 15
12.4 9.63 7.56
50 60 70
1.71 1.19 0.84
20 25 30
5.98 4.77 3.84
80 90 100
0.60 0.45 0.33
DC