Daikin Wall-Mounted Indoor Unit FTXS15HVJU

Warning: This procedure requires trained personnel with PPE!

Install the inverter checker instead of a compressor

Charged voltage of the built-in smoothing electrolytic capacitor dropped to 10 VDC or below?

Terminals removed from the compressor?

Terminals connected to the terminals of the inverter checker without touching each other?

Activate the power transistor test operation from the outdoor unit

Forced operation [ON/OFF] switch pressed for 5 seconds?

Diagnose according to 6 LEDs lighting status

With the power on, operation off, and the connector connected, check the following

Output voltage of about 5 V between pins 1 and 3

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

If NG in step 1 or 2, select the defective part

If OK in both steps 1 and 2, select the part to replace

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 (Refer to Fig.1)?

Is there waveform disturbance near the zero cross (Refer to sections circled in Fig.2)?

Check the connection of connector

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

Check motor control voltage (pins 4 - 3)

Check rotation command voltage output (pins 4 - 2)

Check rotation pulse input (pins 4 - 1)

Sign off on the fan motor connector check

Control voltage between the pins 3 - 4

Rotation command voltage between the pins 2 - 4

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

If NG in step 2 or 4, select the defective part

Sign off on the rotation pulse check