Daikin Air Conditioner RX30NMVJU

Warning: Ensure that the voltage of 320 + 100 V ~ 320 - 50 V is applied

Set operation off and power off. Disconnect the connector S70 or S71

Control voltage between the pins 4 - 3

Rotation command voltage between the pins 4 - 2

Keep operation off and power off

Connect the connector S70 or S71

Rotation pulses at the pins 4 - 1 when the fan motor is rotated 1 turn by hand

Are 4 rotation pulses (0 ~ 15 VDC) input at the pins 4 - 1 when the fan motor is rotated 1 turn by hand?

Conduct the following to check the electronic expansion valve (EV)

Check if the EV connector is correctly connected to the PCB

Turn the power off and on again, and check to see if the EV generates a latching sound

If the EV does not generate a latching sound in the above step 2, disconnect the connector and check the continuity using a multimeter

Check the continuity between the pins 5 - 1, 5 - 2, 5 - 3, 5 - 4. If there is no continuity between the pins, the EV coil is faulty

If the continuity is confirmed in step 3, the outdoor unit PCB (main PCB) is faulty;

Warning: Ensure the power is off before starting the procedure

Voltage between (+) and (-) of the power module

Is the voltage approximately 0V?

Disconnect the compressor harness connector from the outdoor unit PCB

Was the connector successfully disengaged?

Measure resistance between the terminals of the power module and the terminals of the compressor with a multimeter

Resistance between the terminals of the power module and the terminals of the compressor

Sign off on the power module check

Check the connection of connector

Check the motor power supply voltage output

Check the motor control voltage

Check the rotation command voltage

Sign off on the connector output check

Warning: Ensure the voltage between (+) and (-) of the diode bridge (DB1) is approximately 0 V before proceeding

Enter the voltage between (+) and (-) of the diode bridge (DB1)

Measure the resistance between the pins of the DB1 referring to the table below

Enter the resistance between the pins of the DB1

Is the resistance less than 1 kOhm?

If the resistance is less than 1 kOhm, a short circuit occurs on the main circuit

Sign off on the main circuit short check