MITSUBISHI ELECTRIC MSZ-FD25VAS - Manual (Page 31)

31
How to check miswiring and serial signal error D
• Unit cannot operate neither by the remote controller nor by EMERGENCY OPERATION switch.
Indoor unit does not operate.
• POWER lamp flashes ON and OFF every 0.5-seconds.
Outdoor unit does not operate.
Is there rated voltage
in the power supply?
Is there any miswiring,
poor contact, or wire
disconnection of the
indoor/outdoor
connecting wire?
W 1. Miswiring may damage indoor electronic control
P.C. board during the operation.
Be sure to confirm the wiring is correct before the
operation starts.
W 3. Be sure to check this within 3 minutes after turning
ON. After 3 minutes, LED blinks 6 times. Even when
the inverter P.C.board or the outdoor electronic control
P.C.board is normal, LED blinks 6 times after
3 minutes.
(Except for outdoor unit of multi system type)
(Lighted or
not lighted)
No
Yes
No
Yes
Yes
No
Yes
No
Yes
W 2 Be careful to the residual
voltage of smoothing capacitor.
Be sure to release the failure-mode
recall function after checking.
No
No
Yes
No
Yes
Yes
Yes
No Yes
Turn OFF the power supply.
Turn ON the power supply.
Is there rated voltage between
outdoor terminal block S1 and
S2?
Does AREA-L lamp light up?
Press EMERGENCY OPERATION switch once.
Check the power
supply.
A
Turn OFF the power supply.
Check once more if the indoor/outdoor
connecting wire is not miswiring.
Short-circuit outdoor terminal block S2 and
S3.
W 1
B
Turn ON the power supply.
Check the wiring.
Correct them.
Turn OFF the power supply.
Remove the short-circuit between
outdoor terminal block S2 and S3.
Turn ON the power supply.
Is there amplitude of 10 to 20 VDC
between outdoor terminal block S2
and S3? signal>
Is there rated voltage between
indoor terminal block S1 and S2?
Replace the indoor electronic control P.C. board.
Replace the inverter P.C. board or
the outdoor electronic control P.C.board.
W 2
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
contact to the terminal block?
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
contact to the terminal block?
No
Replace the
indoor/outdoor
connecting wire.
Replace the
indoor/outdoor
connecting wire.
Is serial signal
error indicated
6 minutes later?
Yes
No
· Turn OFF inverter-controlled lighting
equipment.
· Turn OFF the power supply and then
turn ON again.
· Press EMERGENCY OPERATION
switch.
B
· Reinstall
either the
unit or the
light each
other away.
· Attach a filter
on remote
control
receiving
section of
the indoor
unit.
A
Is serial signal error indicated 6 minutes later?
No
Does the LED on the inverter P.C. board
or the outdoor electronic control P.C.board
repeat "3.6-second-OFF and 0.8-second-ON
quick blinking"?
W 3
OBH488-2.qxp 07.8.9 4:46 PM Page 31