Mitsubishi Electronics MSZ-A12NA Air Conditioner User Manual


 
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The unit does not operate with the remote controller.
Also, OPERATION INDICATOR lamp does not light up by pressing EMERGENCY OPERATION switch.
Check of indoor electronic control P.C. board and indoor fan motor
C
Yes
No
w1. The fan motor connector's 1 lead wire is red, whereas 3 is black.
w2. Connect "+" of the tester to fan motor connector's 1 lead
wire, and "-" to 3 lead wire, otherwise the resistance cannot be
measured properly.
Yes
No
Does the unit operate with the remote controller?
Does OPERATION INDICATOR lamp light up by
pressing EMERGENCY
OPERATION switch?
Turn OFF the power supply.
Remove indoor fan motor connector CN211 and
vane motor connector CN151 from the indoor electronic
control P.C. board and turn ON the power supply.
Measure the resistance of the horizontal vane
motor coil.
Refer to 8-5.
Measure the resistance between CN211 3
and 4 of the indoor fan motor connector.
Short/open circuit:
Replace the indoor fan motor.
Short/open circuit:
Replace the horizontal vane motor and the indoor
electronic control P.C. board.
Turn OFF the power supply.
Check both parts side and pattern
side of the indoor electronic control P.C.
board visually.
Replace the indoor electronic
control P.C. board.
Are the varistor(NR11) burnt
and the fuse(F11) blown?
Be sure to check both the fuse
and the varistor in any case.
No
Yes
No
Is the fuse(F11) blown only?
Yes
No
Is the resistance 1M"
or more?
Measure the resistance between
1(+) and 3(-) of the indoor fan
motor connector (to CN211 on the
indoor electronic control P.C. board) .
w1,w2
Replace the indoor electronic
control P.C. board
Replace the indoor electronic control
P.C. board and the indoor fan motor.
Is the resistance
approx. 4"?
Measure the resistance of cement
resistance R111 on the indoor electronic
control P.C. board.
Replace the indoor electronic control P.C. board.
Replace the indoor electronic control P.C. board
and the indoor fan motor.
Yes
CN211
Fuse(F11)
Varistor(NR11)
Indoor electronic
control P.C.Board
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