Daikin Outdoor Heat Pump RXS50E3V1B

EV connector correctly connected to the PCB

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

Continuity present when connector is disconnected and checked with a tester

Continuity between pins 1 - 6 and 3 - 6

Continuity between pins 2 - 5 and 4 - 5

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

If continuity is confirmed, the outdoor unit PCB is faulty

Note: The latching sound varies depending on the valve type

Sign off on the electronic expansion valve check

Warning: Be sure to wait for 10 minutes or more after turning off all power supplies before disassembling work.

Pull out the electronic expansion valve coil.

Warning: Be careful not to get yourself burnt with the pipes and other parts that are heated by the gas brazing machine.

Warning: If the refrigerant gas leaks during work, ventilate the room. (If the refrigerant gas is exposed to flames, toxic gas may be generated.)

Caution: From the viewpoint of global environment protection, do not discharge the refrigerant gas in the atmosphere. Make sure to collect all the refrigerant gas.

Before working, make sure that the refrigerant gas is empty in the circuit.

Be sure to apply nitrogen replacement when heating up the brazed part.

Heat up the 2 brazed parts of the electronic expansion valve and remove it.

Output voltage between pins 1 and 3

Number of pulses generated between pins 2 and 3 when the fan motor is operating

If NG in step 1, what is the defect?

If NG in step 2, what is the defect?

If OK in both steps 1 and 2, what is the action?

Warning: This procedure should be performed by a trained technician

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

Upload a photo of the measured waveform

Is the power supply waveform a sine wave?

Is there waveform disturbance near the zero cross?

Sign off on the power supply waveform check

Warning: Be sure to wait for 10 minutes or more after turning off all power supplies before disassembling work.

Disconnect the lead wires of the compressor.

Release the clamp with pliers to detach the compressor lead wires.

Warning: Be careful not to get yourself burnt with the pipes and other parts that are heated by the gas brazing machine.

Warning: If the refrigerant gas leaks during work, ventilate the room. (If the refrigerant gas is exposed to flames, toxic gas may be generated.)

Warning: Since it may happen that the refrigerant oil in the compressor catches fire, prepare wet cloth so as to extinguish fire immediately.

Caution: From the viewpoint of global environment protection, do not discharge the refrigerant gas in the atmosphere. Make sure to collect all the refrigerant gas.