Mitsubishi Electric Mr. Slim MUZ-GE15NA-1, Руководство по обслуживанию

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Is the resistance of thermistor normal? (Refer to 10-6.1.)
Reconnect the connector of thermistor.
Turn ON the power supply and press EMERGENCY OPERATION switch.
No
Replace the thermistor except RT64. When RT64 is
abnormal, replace the inverter P.C. board.
Does the unit operate for 10 minutes or more
without showing thermistor abnormality?
OK. (Cause is poor contact.)
Replace the inverter P.C. board.
Thermistor Symbol Connector, Pin No. Board
Defrost
(MUZ)
RT61 Between CN641 pin1 and pin2
Inverter P.C. board
Discharge temperature RT62 Between CN641 pin3 and pin4
Fin temperature RT64 Between CN642 pin1 and pin2
Ambient temperature RT65 Between CN643 pin1 and pin2
Outdoor heat exchanger temperature RT68 Between CN644 pin1 and pin3
Yes
Yes
No
G Check of outdoor thermistors
H Check of R.V. coil
Disconnect the connector of thermistor in the inverter P.C. board (see
below table), and measure the resistance of thermistor.
MUZ-GE09/12/15NA/NA2/NAH/NAH2, MUZ-GE18NA/NAH, MUZ-GE24NA
First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 10-4.
In case CN721 (
MUZ-GE09/12/15/18
)/CN602 (
MUZ-GE24
) is disconnected or R.V. coil is open, voltage is generated
between the terminal pins of the connector although no signal is being transmitted to R.V. coil. Check if CN721 (
MUZ-
GE09/12/15/18
)/CN602 (
MUZ-GE24
) is connected.
Is there 208/230 VAC between CN721 (
MUZ-
GE09/12/15/18
)/CN602 (
MUZ-GE24
) and
on the inverter P.C. board 3 minutes after the
power supply is turned ON?
No
Yes
Replace the inverter
P.C. board.
Replace the 4-way valve.
Unit operates COOL mode even if it is set to HEAT mode.
Disconnect connector between the
compressor and intelligent power module/
power module 1.
Turn ON the power supply and press
EMERGENCY OPERATION switch twice
(HEAT mode).
MUZ-GE09/12/15NA/NA2/NAH/NAH2, MUZ-GE18NA/NAH, MUY-GE09/12/15NA/NA2, MUY-GE18NA
Thermistor Symbol Connector, Pin No. Board
Defrost
(MUZ)
RT61 Between CN671 pin1 and pin2
Inverter P.C. board
Discharge temperature RT62 Between CN671 pin3 and pin4
Fin temperature RT64 Between CN673 pin1 and pin2
Ambient temperature RT65 Between CN672 pin1 and pin2
Outdoor heat exchanger temperature RT68 Between CN671 pin5 and pin6
MUZ-GE24NA, MUY-GE24NA
1
Intelligent power module:
MUZ-GE09/12/15/18/24NA
,
MUY-GE09/12/15/18/24NA
Power module:
Other models
OBH549F