Mitsubishi Electric MU-GE50VB, Руководство по обслуживанию

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TROUBLESHOOTING 11
3. Troubleshooting procedure
1) First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing ON and OFF to indicate an abnormal-
ity. To make sure, check how many times the OPERATION INDICATOR lamp is flashing ON and OFF before starting
service work.
2) If the electronic control P.C. board seems to be defective, check the copper foil pattern for disconnection and the com-
ponents for bursting and discoloration.
Lead wiring
Housing point
11-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for mis-wiring.
2. Take care of the following during servicing.
1) Before servicing the air conditioner, be sure to turn OFF the main unit first with the remote controller, and then after
confirming the horizontal vane is closed, turn OFF the breaker and/or disconnect the power plug.
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 electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
MU-GE50VB
MUH-GE50VB
SERVICE FUNCTIONS 10
10-1. COMPULSORY DEFROSTING MODE FOR SERVICE
By short circuit of the connector JPDS and JPSG on the outdoor deicer P.C. board, defrosting mode can be accomplished
regardless of the defrost interval restriction. (Refer to 11-4.)
Defrost thermistor RT61 must read below -3°C.
10-2. CHANGE IN DEFROST SETTING
<JRF> When the JRF wire of the deicer P.C. board is cut, the defrost interval time will be changed.
<JRG> When the JRG wire of the deicer P.C. board is cut, the defrost temperature will be changed. (Refer to 11-4.)
Jumper wire
JRF
JRG
MODEL Change point
Defrost interval time changes from 40 minutes to 15 minutes.
Defrost start temperature changes from -3°C to 0°C.
MUH-GE50VB
MUH-GE50VB