Daikin Cooling-Only Outdoor Unit RKN09AXVJU

Warning: This check requires trained personnel with PPE!

Measure the power supply waveform between No. 1(Live) and No. 2(Neutral) on the terminal board

Upload the oscilloscope reading

Is the power supply waveform a sine wave?

Is there waveform disturbance near the zero cross?

Sign off on the power supply waveforms check

Ensure that the voltage of 320 ± 30 V is applied.

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

Check that the voltage between the pins 4 & 7 is 320 VDC.

Check that the control voltage between the pins 3 & 4 is 15 VDC.

Check that the rotation command voltage between the pins 2 & 4 is 0 - 6.5 VDC.

Keep operation off and power off. Connect the connector S71.

Check whether 4 pulses (0 ~ 15 VDC) are output at the pins 1 - 4 when the fan motor is rotated 1 turn by hand.

When the fuse is melted, check the outdoor fan motor for proper function.

If NG in step 2 : Defective PCB and replace the outdoor unit PCB.

EXV connector correctly connected to PCB

EXV generates a latching sound when power is turned off and on

If EXV does not generate a latching sound, proceed to next step

Continuity confirmed when connector is disconnected and checked with a multimeter

Check the continuity between pins

If there is no continuity between the pins, EXV coil is faulty

Continuity confirmed between pins

If the continuity is confirmed, outdoor PCB is faulty

Sign off on the Electronic Expansion Valve Check

In order to protect the environment, be sure to conduct pump down operation when relocating or disposing of the unit.

Valve caps removed from the liquid stop valve and the gas stop valve?

Forced cooling operation carried out?

Liquid stop valve closed with a hexagonal wrench?

Gas stop valve closed and forced cooling operation stopped?

Sign off on the pump down maintenance

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

Enter the resistance between the pins of the DB1

Is the resistance ∞ or less than 1 kW?

If the resistance is ∞ or less than 1 kW, a short circuit occurs on the main circuit.

Sign off on the main circuit short check