Daikin Indoor Cooling/Heating Unit FXMQ18PVJU

Warning: Ensure power is OFF before starting the procedure

Remove all the wiring connected to the PCB where power transistors are mounted on

Prepare the analog type of multimeter. For the digital type of multimeter, those with diode check function are available for the checking

Wait for 10 minutes or more before making measurement of resistance

Select the type of multimeter used

If using the analog type of multimeter, make measurement in resistance measurement mode in the x1 kΩ range

If using the digital type of multimeter, make measurement in diode check mode

Warning: This procedure requires trained personnel with PPE!

Choose the type of vacuuming and dehydration

Vacuum pump enables vacuuming down to –100.7 kPa (–14.6 psi)?

Enter the vacuum pump run time in hours

Degree of vacuum reached –100.7 kPa (–14.6 psi) or less?

Leak tests conducted if vacuum did not reach –100.7 kPa (–14.6 psi) or less after 3 hours?

Compressor left at the degree of vacuum of –100.7 kPa (–14.6 psi) or less for a period of 1 hour or more?

Vacuum gauge reading did not rise after leaving the compressor in vacuum state?

Enter the amount of refrigerant charged

Superheated degree of suction gas

Superheated degree of suction gas

Electronic expansion valve open?

Warning: This procedure requires trained personnel with PPE!

Electronic Expansion Valve Coil checked

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

Measure the resistance value between pins

No continuity between White and Yellow

Resistance value between White and Orange

Resistance value between White and Red

Resistance value between Yellow and Blue

Resistance value between Yellow and Brown

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

Enter the suction gas superheated degree

Enter the discharge gas superheated degree

Does the superheat operation meet the judgement criteria?

Sign off on the superheat operation check