135
How to check mis-wiring and serial signal error (when outdoor unit does not work)
E
Mis-wiring is indicated.
(0.5-sec. ON, 0.5-sec. OFF)
1. Turn OFF the power supply
(indoor/outdoor unit)
and disconnect in-out connecting wire on indoor side.
2. Short-circuit between indoor terminal block
N
and
3
.
3. Turn ON the power supply
(indoor unit)
and press once EMERGENCY OPERATION switch.
During EMERGENCY OPERATION,
is there 10V DC between both ends
of R601? (See page 143.)
(By tester, the stylus is between 5 ~10V)
Serial signal error is indicated.
(0.5-sec. ON, 2.5-sec. OFF)
Start
Turn OFF the power supply(indoor/outdoor unit).
No
No
Is there 20V DC between both ends of
R132 on indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20V. )
•Turn OFF the power supply(indoor unit).
•Connect ON in-out connecting wire.
Is the outdoor unit "MUH or MXZ" type?
•Turn ON the power supply(indoor/outdoorunit).
•Press once EMERGENCY OPERATION switch.
Is this mis-wiring, poor contact,
or wire disconnection?
Make them sure.
Replace the indoor electronic
control P.C. board.
Turn ON the power supply(outdoor unit).
Is there 220-240V AC between outdoor
terminal block
L
-
N
?
No
Check the outdoor power supply,
power supply cord and
connection.
Is there 5V DC between J8
-
-J9
+
?
(See page 143.)
Yes
Turn ON the power supply(indoor unit).
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.
(See page 143.)
Replace the DEICER P.C. board.
Yes
Yes
Yes
3 min. later, what self-check result is
displayed on Operation Indicator
lamp on indoor unit?
w
2
Set the switch(SW2-
2
) on the indoor electronic
control P.C. board to MU& MUX type.
(See page 121.)
w
1
Yes
Does the unit operate?
Ok
Yes
No
No
Follow the chart
on page 123.
w
2 Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self -check to be displayed in 3 seconds.
w
1 Set the switch(SW2-
2
) on indoor electronic control P.C. board to
MU type, when the outdoor unit is MU type.
If the setting is MUH type, the unit does not work.
Is the outdoor unit "MUH" type?
Yes
No
Refer to
T
Check of mis-wiring
or mis-piping.(See page 141)