Mitsubishi Electric MSZ-GS06NA - U1 Service Manual page 51

MSZ-GS18/24NA
MSY-GS18/24NA
Is the bus-bar voltage of the inverter P.C. board or the outdoor electronic control P.C. board normal?
(Refer to "TEST POINT DIAGRAM AND VOLTAGE" in the outdoor service manual.)
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"? *3
Is there amplitude of 10 to 20 V DC between the indoor terminal block
S2 and S3? <Confirmation of serial signal>
A
• Turn OFF inverter-controlled lighting
equipment.
• Turn OFF the power supply and then
turn ON again.
• Press the emergency operation switch.
• Reinstall
either the unit
or the light
away from
Is serial signal
each other.
• Attach a filter
error indicated 6
No
minutes later?
on remote
control
Yes
receiving
section of the
B indoor unit.
OBH874A
Turn OFF the power supply.
Is there rated voltage in the power supply?
Turn ON the power supply.
Is there rated voltage between outdoor terminal block S1 and S2?
Press the emergency operation switch once.
Does the OPERATION INDICATOR lamp light
up? <Confirmation of the power to the indoor
unit>
Is serial signal error indicated 6 minutes later?
Turn OFF the power supply.
Check once more if the indoor/outdoor
B
connecting wire is not miswiring.
Bridge the outdoor terminal block S2 and
S3. *1
Turn ON the power supply.
Turn OFF the power supply.
Remove the bridge between outdoor terminal block S2 and S3.
GS18
Turn on the power supply.
Yes
Is there 2 V DC or less between CN10A
and GND (-) on the indoor electronic control
P.C. board?
Yes
Is there 2 V DC or less between
CN10A
indoor electronic control P.C. board?
Replace the indoor power
P.C. board.
No
Yes
Yes
No
Yes
No
Yes
A
*1. Miswiring may damage indoor electronic control P.C.
board during the operation.
Be sure to confirm the wiring is correct before the opera-
tion starts.
*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)
Yes
No
(Lit or
Yes
not lit)
GS24
Replace the indoor electronic control P.C. board.
No
(+)
No
(+) and GND (-) on the
No Yes
Replace the indoor electronic
control P.C. board.
51
Check the power supply.
Check the wiring.
No
Is there any miswiring,
poor contact, or wire dis-
Correct them.
Yes
connection of the indoor/
outdoor connecting wire?
No
No
Replace the inverter P.C. board or the outdoor
electronic control P.C. board. *2
*2. Be careful of the residual voltage of smoothing
capacitor.
Is there 2 V DC or less between
CN10A (+) and GND (-) on the
indoor electronic control P.C. board?
No
Yes