Daikin Indoor Cooling/Heating Unit FXMQ36PVJU

Overload control causing insufficient cooling capacity

Superheated degree of suction gas

Compressor lower in discharge pipe temperature despite of pressure loads

In heating, the temperature of discharge air through the subcooled section becomes lower

Superheated degree of suction gas

Superheating temperature control in cooling is conducted by indoor unit electronic expansion valve

Is the indoor unit electronic expansion valve functioning properly?

Superheating temperature control in heating is conducted by outdoor unit electronic expansion valve (main)

Is the outdoor unit electronic expansion valve functioning properly?

Judgement criteria of superheat operation: Suction gas superheated degree: 10°C (50°F) and over.

Enter the suction gas superheated degree

Judgement criteria of superheat operation: Discharge gas superheated degree: 45°C (113°F) and over, except immediately after compressor starts up or is running under drooping control

Enter the discharge gas superheated degree

Enter any other conditions that may affect the superheat operation

Warning: This procedure requires trained personnel with PPE!

Compressor PI control in cooling

Low pressure protection control

Superheated degree control in cooling

Superheated degree control in heating

Warning: Ensure power is OFF before starting the procedure

All wiring removed from the PCB

Power supply turned OFF and 10 minutes or more have passed

Measurement made in resistance mode in the x1 kΩ range (for analog multimeter)

Measurement made in diode check mode (for digital multimeter)

Sign off on the power transistor check

Remove the connector for electronic expansion valve (X7A) from PCB

Check continuity between White and Yellow

Measure resistance value between White and Orange

Measure resistance value between White and Red

Measure resistance value between Yellow and Blue

Measure resistance value between Yellow and Brown

Sign off on the Electronic Expansion Valve Coil Check