49
Yes
Yes
How to check mis-wiring and serial signal error (when outdoor unit does not work)
E
1. Turn OFF power supply.
2. Turn ON power supply.
3. Press EMERGENCY OPERATION switch.
3 min. later, when 52C contactor turns ON, what self-check result
is displayed on OPERATION INDICATOR lamp indoor unit?
w
1
Start
1. Turn OFF power supply and disconnect indoor/ outdoor unit connecting wire of the indoor unit.
2. Short-circuit between indoor terminal block and .
3. Turn ON power supply and press EMERGENCY OPERATION switch.
•Turn OFF power supply.
•Re-connect indoor/ outdoor unit connecting wire.
•Turn ON power supply.
3 minutes later, when EMERGENCY OPERATION switch is pressed
and 52C contactor turns ON, is there 220-240V AC between outdoor
terminal block and ?
Is there 5V DC between J9 -J8 (MUCFH-13/18NV)/
J101 -J401 (MUCFH-24NV) on the deicer P.C. board?
Is there 10V DC between both ends of R601 on the deicer P.C.
board?
(By tester, the stylus is between 5 ~10V DC)
Replace the deicer P.C. board.
Rectify indoor/ outdoor unit
connecting wire.
Check and rectify fuse and varistor on the
deicer P.C. board.
Rectify indoor/ outdoor unit
connecting wire.
Replace the indoor electronic control
P.C. board.
w
1 Short circuit of JPG and JPS on the
electronic control P.C. board enables
self-check to be displayed in 3 seconds.
Serial signal error is indicated.
(1-sec.ON, 2.5-sec.OFF)
Repair wiring.
Is there mis-wiring, poor contact, or wire disconnection?
N
3
Is there 20V DC between both ends of R132 when
52C contactor turns ON?
(By tester, the stylus is between 0 ~ 20V.)
2
N
+
–
Yes
Yes
No
No
No
No
No
Yes
Mis-wiring is indicated.(1-sec.ON,1-sec.OFF)
When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second or flashes once.
Outdoor unit does not operate.
+
–
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