Mitsubishi Electric MUZ-GA25VA-E1 Service Manual page 37

Mitsubishi ilmalämpöpumput huoltaa ja korjaa: Jäähdytinpalvelu RefGroup Oy
Outdoor fan motor does not operate.
Check of outdoor fan motor
I
-
MUZ-GA35VA
E1
-
MUZ-GA35VAH
E1
Is the resistance
between each terminal of
outdoor fan motor
No
Replace the outdoor fan
motor.
Inverter does not operate.
Check of power supply
J
Disconnect the connector
(CN61) between compressor and
intelligent power module.
Turn ON power supply and press
EMERGENCY OPERATION
switch.
Does the left lamp of
OPERATION INDICATOR
lamp on the indoor unit
light up?
Yes
Is there voltage
280V ~ 370V DC
between DB61 (+) and
DB61 (–) on the
inverter P.C. board?
Refer to 11-7.1.
No
Check the electric
parts in main circuit.
Disconnect CN932
Yes
from the inverter
P.C. board.
Inverter P.C. board
(Solder side)
CN931
CN932
Rectify indoor/ outdoor
connecting wire.
Yes
Is there voltage 230V AC
No
between the indoor
terminal block S1 and
S2?
Dose LED on the inverter
Yes
P.C. board light up or
flash? Refer to 11-7.1.
Yes
Ok.
If flash, refer to
11-4.
www.ilmalämpöpumput.com
Turn ON the
power supply.
No
( Fixed to either 5V or 0V DC)
Indoor/ outdoor
connecting
wire
Replace the indoor
No
electronic control
P.C. board.
No
Replace the inverter
P.C. board.
DB61
Inverter P.C. board
(Solder side)
37
Rotate the outdoor fan slowly
by hand, and measure the
voltage of CN931 (Measurement
of feedback output).
Between 1(+) and 5(-)
Between 2(+) and 5(-)
Between 3(+) and 5(-)
Does the voltage between
each terminal become 5V
and 0V DC repeatedly?
Yes
Does the outdoor fan
rotate smoothly?
No
Yes
Ok
Outdoor terminal block
S3
S2
S1
280V~370V DC