Daikin Outdoor Unit Wall Mounted Type RXJ25MV1B

Characteristics: Inverter analyzer: RSUK0917C

Warning: Be sure to turn the power off before starting the procedure.

Install an inverter analyzer instead of a compressor.

Note: Make sure the charged voltage of the built-in smoothing electrolytic capacitor drops to 10 VDC or below before carrying out the service work.

Remove the terminals from the compressor.

Terminals removed from the compressor?

Connect the terminals to the terminals of the inverter analyzer. Be careful not to let the terminals (U,V,W) touch each other. Otherwise, high voltage is applied.

Check No.20: Main Circuit Short Check

Voltage between (+) and (–) of the diode bridge (DB1) is approximately 0 V

Enter the resistance between the pins of the DB1

Resistance is ∞ or less than 1 kΩ

Short circuit occurs on the main circuit?

Sign off on the main circuit short check

EV connector correctly connected to the PCB

EV generates a latching sound when power is turned off and on again

Continuity confirmed when connector is disconnected and checked with a multimeter

Check the continuity between the pins

Sign off on the electronic expansion valve check

Measure the power supply waveform between No. 1 and No. 2 on the terminal board

Check if the power supply waveform is a sine wave (Fig.1)

Check if there is waveform disturbance near the zero-cross (sections circled in Fig.2)

Sign off on the power supply waveforms check

Check the connection of connector

Check the motor power supply voltage output (pins 4 - 7)

Check the motor control voltage (pins 4 - 3)

Check the rotation command voltage (pins 4 - 2)

Check the rotation pulse (pins 4 - 1)

Sign off on the fan motor connector output check