Troubleshooting - Mitsubishi Electric SUZ-SWM40VA Technical & Service Manual

10

TROUBLESHOOTING

SUZ-SWM40VA.TH
SUZ-SWM60VA.TH
SUZ-SWM80VA.TH
10-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following items:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for miswiring.
2. Take care of the following during servicing.
1) Before servicing the air to water heat pump, be sure to turn OFF the main unit first with the remote controller, and turn off the
breaker.
2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the electronic
control P.C. board.
3) When removing the electrical parts, be careful of the residual voltage of smoothing capacitor.
4) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
5) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
3. Troubleshooting procedure
1) Check if the OPERATION INDICATOR lamp on the outdoor P.C. board is blinking on and off to indicate an abnormal-
ity. To make sure, check how many times the abnormality indication is blinking on and off before starting service work.
2) Before servicing check that the connector and terminal are connected properly.
3) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.
4) When troubleshooting, refer to "10-2. TROUBLESHOOTING CHECK TABLE" and "10-3. HOW TO PROCEED "SELF-
DIAGNOSIS"".
OCH718A
Lead wire
Housing point
19