Mitsubishi Electronics MSH-A18ND Air Conditioner User Manual


 
16
How to check mis-wiring
D
1. Turn OFF the power supply (outdoor unit) and disconnect indoor and outdoor connecting
wire 3 on indoor side.
2. Short-circuit terminal block N-3 by lead wire.
3. Turn ON the power supply (outdoor unit) and press EMERGENCY OPERATION switch once.
During EMERGENCY OPERATION, is there
10V DC between both ends of R601 on the
deicer P.C. board?
(By tester, the stylus is between 5 ~10V.)
Refer to outdoor unit service manual.
Start
No
No
Is there 20V DC between both ends of
PS132 on the indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20V. )
Turn ON the power supply.
(outdoor unit)
Press EMERGENCY OPERATION switch once.
Is this mis-wiring, poor contact,
or wire disconnection?
Correct them.
Replace the indoor electronic
control P.C. board.
No
Replace the deicer P.C. board.
Yes
No
Make the wiring between CN730
on the deicer P.C. board and
outdoor terminal block correct.
Replace the deicer P.C. board.
Yes
Is there 5V DC between J205 + -J101 -
/ J101 + -J401 - on the deicer P.C. board?
Yes
Yes
After 3 minutes, mis-wiring is indicated
(0.5-second ON, 0.5-second OFF)
on OPERATION INDICATOR
lamp on indoor unit.w
w Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self -check to be displayed in 3 seconds.
Turn OFF the power supply.
(outdoor unit)
Connect ON indoor/ outdoor connecting
wire.
Turn ON the power supply. (outdoor unit)
When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit doesnt operate.
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