Trouble Shooting 6; Thermistor Error - Fujitsu As*A09Lkc Service Instructions Manual

Trouble shooting 6

OUTDOOR UNIT Error Method:
Outdoor Discharge Pipe Temperature

Thermistor Error

Detective Actuators:
Outdoor Unit Inverter PCB
Discharge Pipe Temperature Thermistor
Forecast of Cause :
1. Connector connection failure
Check Point 1 : Check connection of connector
Check if connector is removed.
Check if connector is erroneous connection.
Check if thermistor cable is open.
>> Upon correcting the removed connector or mis-wiring, reset the power.
OK 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 OK
Check Point 3 : Check voltage of Inverter PCB (DC5.0V)
Make sure circuit diagram of outdoor unit and check terminal voltage at thermistor (DC5.0V)
AO*R09LKC
BLACK
1 1
BLACK
2 2
BLACK
3 3
BLACK
4 4
BLACK
1 1
2 2
BLACK
3 3
If the voltage does not appear, replace
Indicate or Display:
Refer to error code table.
Detective details:
When Discharge Pipe Temperature Thermistor open or short-circuit
is detected at power ON or while running the compressor.
2. Thermistor failure
0 5 10
168 130 101 79.0
70 80 90 100
8.7 6.3 4.6 3.4
THERMISTOR
( HEAT EXCHANGER )
THERMISTOR
( DISCHARGE PIPE )
THERMISTOR
( OUTDOOR TEMP. )
Inverter PCB
.
02-08
3. Inverter PCB failure
15 20 30 40
63.0 40.0 26.3
120
2.0
AO*R12LKC
BLACK
1 1
BLACK
2 2
BLACK
3 3
BLACK
4 4
BLACK
1 1
2 2
BLACK
3 3
50 60
17.8 12.3
THERMISTOR
( HEAT EXCHANGER )
THERMISTOR
( DISCHARGE PIPE )
THERMISTOR
( OUTDOOR TEMP. )