28
<Thermistor Characteristic graph>
Room temperature thermistor(TH1)
Pipe temperature thermistor/liquid(TH2)
Condenser/evaporator temperature
thermistor(TH5)
Thermistor R
0
=15k
± 3%
Fixed number of B=3480
± 2%
t(
)Rt=15exp { 3480( ) }
7Û)5W H[S^
`
0
Û)
N
10
Û)
N
20
Û)
N
25
Û)
N
30
Û)
N
40
Û)
N
Thermistor for
lower temperature
1
273+t
1
273
10-6-1. Thermistor
Notes
· High voltage is applied to the connecter (CNMF) for the fan motor. Give attention to the service.
· Do not pull out the connector (CNMF) for the motor with the power supply on.
(It causes trouble of the indoor controller circuit
board and fan motor.)
Self check
Symptom : The indoor fan cannot turn around.
No
NG
NG
Wiring contact check
Contact of fan motor connector (CNMF)
Check the fuse (FUSE) on indoor
controller board.
Power supply check (Remove the connector (CNMF))
Measure the voltage in the indoor controller circuit
board.
TEST POINT
:
V
DC
(between 1 (+) and 4 (-) of the fan connector): V
DC
DC294~325V
TEST POINT
:
V
CC
(between 5 (+) and 4 (-) of the fan connector): V
CC
DC15V
Wiring recovery
Replace drain pump (DP).
Replace indoor controller board.
Replace the fan motor.
Replace indoor controller board (I.B).
Replace fan motor (MF).
Replace indoor
controller board.
Replace the fan motor.
Is the voltage normal?
Is there no contact failure?
Yes
Yes
No
Did the fuse blow?
Check the drain pump (DP).
Is the resistance between
terminals normal?
No
Yes
Yes
No
Check the operation of fan.
END
Yes
OK
Check the operation.
END
OK
Check method of DC fan motor (fan motor / indoor controller circuit board)
10-6-2. DC Fan motor (FAN MOTOR/ INDOOR CONTROLLER BOARD)
0
10
20
30
40
50
-20 -10 0
10 20 30 40 50
-4 -14 32 50 68 86 104 122
F
Temperature
Resistance (k
)
<Thermistor for lower temperature>
1
273+
1
273
T-32
1.8
