Mitsubishi Electronics MUZ-GB50VA service manual Troubleshooting

Models: MUZ-GB50VA

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9-3. Relation between main sensor and actuator <MUZ-GB50>

 

 

 

Actuator

 

Sensor

Purpose

Compressor

LEV

Outdoor

R.V. coil

 

 

fan motor

Discharge temperature thermistor

Protection

 

 

 

 

Indoor pipe temperature thermistor

Defrosting Protection

 

 

 

 

Defrost thermistor

Defrosting

 

 

 

 

Fin temperature thermistor

Protection

 

 

 

 

Outdoor heat exchanger temperature

Protection

 

 

 

 

Ambient temperature thermistor

Protection

 

 

 

 

10 TROUBLESHOOTING

MUZ-GB50VA

10-1. 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 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 electrical parts, be careful to 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.

Lead wiring

Housing point

3.Troubleshooting procedure

1)First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality. To make sure, check how many times the abnormality indication is flashing 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., 10-3. and 10-4.

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Mitsubishi Electronics MUZ-GB50VA service manual Troubleshooting, Relation between main sensor and actuator MUZ-GB50