31
Check of outdoor thermistors
G
POWER lamp flashes 6-time.
The thermistors in the outdoor unit are abnormal.
Check of R.V. coil
H
Disconnect connector (CN61) between
the compressor and intelligent power
module.
Turn ON the power supply and press
EMERGENCY OPERATION switch
twice (HEAT mode).
Is there 230 VAC between CN721
1
and
2
on the inverter P.C.board 3 minutes
after the power supply is turned ON?
Yes
No
Replace the inverter
P.C.board.
Replace the 4-way valve.
Replace the 4-way valve.
Disconnect connector (CN61) between
the compressor and the intelligent power
module.
Turn ON the power supply and press
EMERGENCY OPERATION switch once
(COOL mode).
Is there 230 VAC between CN721
1
and
2
on the inverter P.C.board 3 minutes
after the power supply is turned ON?
No
Yes
w
First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 11-4.
w
In case CN721 is not connected or R.V. coil is open, voltage is generated between the
terminal pins of the connector although any signal is not being transmitted to R.V. coil.
Check if CN721 is connected.
CN721
Inverter P.C.board
(Soldered side)
Replace the inverter
P.C.board.
Unit operates COOL mode even if it is set to HEAT mode.
Unit operates HEAT mode even if it is set to COOL mode.
Yes
Yes
No
No
Reconnect the connector of thermistor.
Turn ON the power supply and press EMERGENCY OPERATION switch.
Defrost
Discharge temperature
Fin temperature
Ambient temperature
Outdoor heat exchanger termperature
Thermistor
Board
Inverter P.C. board
RT61
RT62
RT64
RT65
RT68
Between CN641 pin1 and pin2
Between CN641 pin3 and pin4
Between CN642 pin1 and pin2
Between CN643 pin1 and pin2
Between CN644 pin1 and pin3
Is the thermistor normal? (Refer to 11-6.1.)
Does the unit operate for 10 minutes or more without
showing thermistor abnormality?
Replace the thermistor except RT64.
When RT64 is abnormal, replace the inverter P.C. board.
OK.
(Cause is poor contact.)
Replace the inverter P.C.board.
Disconnect the connector of thermistor in the outdoor P.C.board (see below table),
and measure the resistance of thermistor.
OBH489--2.qxp 07.8.9 11:54 AM Page 31
Содержание MUZ-FD25VA
Страница 2: ...2 ...
Страница 8: ...8 6 WIRING DIAGRAM MUZ FD25VA MUZ FD35VA ...
Страница 9: ...9 MUZ FD25VAH MUZ FD35VAH ...
Страница 42: ...42 ...
Страница 43: ...43 ...