Daikin Ceiling-Duct Inverter Unit FDKS50CVMB

Warning: This procedure requires trained personnel with PPE!

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

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.

Warning: Disconnect the connectors of the thermistors from the PCB before proceeding

Thermistors disconnected from the PCB

Measure the resistance of each thermistor

Upload a photo of the tester reading

Select the model of the thermistor

Sign off on the thermistor resistance check

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

Preparation: Remove the top panel and the front panel according to the “Removal of Outer Panels”. This procedure is not necessary to remove the outdoor fan only.

Remove the screw of the shield plate.

Unfasten the 2 hooks and remove the shield plate.

Unfasten the 4 hooks of the electrical box cover and remove it.

Disconnect the connector for the fan motor [S70].

Release the fan motor lead wire from the 7 hooks.

Remove the washer fitted nut of the outdoor fan. Note: The screw has reverse winding. Nut size: M6. When reassembling, align mark of the outdoor fan with D-cut section of the motor shaft.

Remove the lower 2 screws from the fan motor first. Note: Be sure to remove the lower screws first. If the upper screws are removed first, the fan motor, the center of gravity of which is toward the front, may tilt down or fall, getting you injured.

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