Mitsubishi Electric MSZ-G09SV-E1 Service Manual page 55

K
Check of R.V. coil
Cooling operates when heating is expected.
First, measure resistance of the R.V. coil to check if it is defective or not.
If the connector CN 721 is not connected or the R.V. coil is open, the voltage occurs between the terminals even when
the control is OFF.
Disconnect the connector between the
compressor and transistor module.
Turn ON the power supply to indoor unit,
and press twice (heating) the
EMERGENCY OPERATION switch.
L
Check of outdoor fan motor
Outdoor fan motor does not work.
Disconnect the connector CN 771 on the relay P.C.
board.
Disconnect the connector between compressor and
transistor module.
Turn ON the power supply to indoor unit and press
the EMERGENCY OPERATION switch.
Outdoor terminal block
N
In-out
2
connecting
wire
3
Relay P.C. board
3 minutes after power
ON, is there voltage of
230V AC between
outdoor terminal block
2 and N?
Yes
Fan
motor
1 2 3
4 5 6
CN771
Outdoor terminal block
N
In-out
connecting
2
wire
3
3 minutes after
power ON, is there
No
voltage of 230V AC
between CN 721 1
and 2 on the relay
P.C. board?
Yes
Replace the
R.V. coil.
Repair in -out
connecting wire.
Yes
Press the
EMERGENCY
No
OPERATION switch
again.
Does the 52C work?
Is there voltage of
approx. 230V AC either
between 1 and 3 or
between 3 and 5 at CN
771?
Yes
Replace the
outdoor fan motor.
55
R.V. coil
230V AC
1 2
CN721
Relay P.C. board
Replace the
relay P.C. board.
Replace the indoor
No
electronic control
P.C. board.
No
Replace the
relay P.C. board.