Service manual

TROUBLESHOOTING11

MCF-13NV -

MCF-18NV -

MCF-24NV -

11-1. CAUTIONS ON TROUBLESHOOTING

11-1-1. Before troubleshooting, check the followings:

1) Check the power supply voltage.

2) Check the indoor/outdoor connecting wire for mis-wiring.

11-1-2. Take care the followings during servicing.

1) Be sure to unplug the power cord before removing the air inlet grille, the front panel, the cabinet, the top panel, and

the electronic control P.C. boards.

2) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the

components.

3) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.

11-1-3. Troubleshooting procedure

1) First, check if the Power monitor lamp on the indoor unit is flashing on and off to indicate an abnormality. To make

sure, check the abnormality indication for 2 times before starting service work.

2) Before servicing check that the connectors and terminals 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.

3) When troubleshooting, refer to the flow chart and the check table on page 36.

11-1-4. How to replace batteries

Weak batteries may cause the remote controller malfunction.

In this case, replace the batteries to operate the remote controller normally.

1 Remove the front lid and insert batteries.

Then reattach the front lid.

Insert the negative pole

of the batteries first.

Check if the polarity of

the battereis is correct.

RESET button

2 Press the RESET button with tip end of ball point

pen or the like, and then use the remote controller.

MUCF-13NV -

MUCF-18NV -

MUCF-24NV -

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