132
Check of R.V. coil
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
1. Disconnect the lead wire leading to the compressor.
2. 3 minutes after turning ON the power supply, start EMERGENCY
OPERATION in HEAT mode.
Is there voltage of 230V AC between pin1 and
pin 2 at connector CN912?
Turn OFF the power supply of indoor and outdoor unit.
1. Turn OFF the power supply of indoor and outdoor unit, and
disconnect the connector CN933 or CN781.
2. 3 minutes after turning ON the power supply, start
EMERGENCY OPERATION in HEAT mode.
Replace the 4-way valve.
Replace the power P.C. board or
the noise filter P.C. board.
Replace the R.V. coil.
Is there voltage 12V DC
between the connector CN933
pin 1 (+) and pin 3 (-) or the
connector CN781
pin 5 (+) and pin 3 (-) ?
Replace the inverter P.C.
board or the electronic
control P.C. board.
Disconnect the connector
CN912. Is there normal
resistance to R.V. coil?
(Refer to 13-5.)
1. Disconnect the lead wire leading to the compressor.
2. 3 minutes after turning ON the power supply, start EMERGENCY
OPERATION in COOL mode.
Is there voltage of 230V AC between pin1 and
pin 2 at connector CN912?
1. Turn OFF the power supply of the indoor and the outdoor
unit, and disconnect the connector CN933 or CN781.
2. 3 minutes after turning ON the power supply, start
EMERGENCY OPERATION in COOL mode.
Replace the 4-way valve.
Replace the power P.C.board or
the noise filter P.C. board.
Is there voltage 12V DC
between the connector CN933
pin 1 (+) and pin 3 (-) or the
connector CN781
pin 5 (+) and pin 3 (-) ?
Replace the inverter P.C. board or the outdoor electronic control P.C. board.
If the connector CN912 is not connected or R.V. coil is open, voltage
occurs between terminals even when the control is OFF.
• When heating operation does not work.
• When cooling operation does not work.
The cooling operation or heating operation does not operate.
Power P.C. board
Inverter P.C. board
CN912
CN781
CN933
Noise filter P.C. board
Outdoor electronic control
P.C. board
MXZ-2A
MXZ-3A/4A/5A
Summary of Contents for MXZ-2A30VA
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