Obh799 - Mitsubishi Electric MSZ-AP15VF-E1 Service Manual

D How to check miswiring and serial signal error
A
• Turn OFF inverter-controlled lighting
equipment.
• Turn OFF the power supply and then
turn ON again.
• Press EMERGENCY OPERATION
switch.
• Reinstall
either the unit
or the light
away from
each other.
Is serial signal
• Attach a fi lter
error indicated 6
No
on remote
minutes later?
control receiv-
Yes
ing section
of the indoor
unit.
B

OBH799

Turn OFF the power supply.
Is there rated voltage in
the power supply?
Yes
Turn ON the power supply.
Is there rated voltage between
the outdoor terminal block S1
and S2?
Yes
Press EMERGENCY OPERATION switch once.
Does the left lamp of OPERATION
INDICATOR lamp light up?
<Confirmation of the power to the indoor unit>
Yes
Is serial signal error indicated 6 minutes later?
Yes
A
Turn OFF the power supply.
Check once more if the indoor/outdoor
connecting wire is not miswiring.
B
Bridge the outdoor terminal block S2 and
S3.
1
Turn ON the power supply.
Does the LED on the outdoor electronic
control P.C. board repeat "3.6-second-OFF
and 0.8-second-ON quick blinking"?
Yes
Turn OFF the power supply.
Remove the bridge between
the outdoor terminal block S2 and S3.
Turn ON the power supply.
Is there amplitude of 10 to 20 V DC
between the outdoor the terminal
block S2 and S3?
<Confirmation of serial signal>
Yes
Is there rated voltage between the
indoor terminal block S1 and S2?
<Confirmation of power voltage>
Yes
Replace the indoor electronic control P.C. board.
Be sure to release the failure-mode
recall function after checking.
27
No
Check the power
supply.
No
Check the wiring.
No
Is there any miswiring,
poor contact, or wire
No
disconnection of the
indoor/outdoor
connecting wire?
No
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.
Replace the outdoor electronic control
No
P.C. board.
(Lighted
2
or
2 Be careful of residual
not lighted)
voltage of smoothing capacitor.
No
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
No
contact to the terminal block?
No
Yes
Correct them.
Replace the
Yes
indoor/outdoor
connecting wire.