Daikin Indoor Unit Wall Mounted Type CTXG50EV1BS

Check No.10: Power Supply Waveforms Check

Measure the power supply waveform between pins 1 and 3 on the terminal board

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

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

Sign off on the power supply waveforms check

Warning: Never touch any live parts for at least 10 minutes after turning off the circuit breaker.

If unavoidably necessary to touch a live part, make sure the power transistor's supply voltage is below 50 V using the tester.

Enter the supply voltage of the power transistor

Is the supply voltage below 50 V?

For the UVW, make measurements at the Faston terminal on the board or the relay connector.

Upload a photo of the Faston terminal on the board or the relay connector.

Sign off on the power transistor check

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

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

1. Restore the piping by nonoxidation brazing.

In case of you cannot use the nitrogen gas, restore as quickly as possible.

2. It is required to prevent the carbonization of the oil inside the four way valve and the deterioration of the gaskets affected by heat. For the sake of this, wrap the four way valve with wet cloth and provide water so that the cloth will not be dried and avoid excessive heating. (Keep below 120°C)

Be careful so as not to break the pipes by pressing it excessively by pliers when withdrawing it.

In case of the difficulty with gas brazing machine

1. Disconnect the brazed part where is easy to disconnect and restore.

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

Remove the fan motor fixing plate.

Remove the outer panels and plates.

Take out the fan motor fixing plate toward yourself.

When assembling, fit the lower hooks.

Loosen the washer fitted nut to remove the propeller fan.

When assembling, align mark of the propeller fan with D-cut section of the motor shaft.

When assembling, make sure ! mark of the fan motor goes up.

With the power ON, operation OFF, and the connector connected, check the following

Output voltage between pins 1 and 3

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

If failure, identify the faulty part