Daikin Indoor Unit Multi-Split Type Air Conditioner FTXR09TVJUS

Conduct the following to check the electronic expansion valve (EV).

1. Check if the EV connector is correctly inserted in the PCB. Match the EV unit number and the connector number.

2. Turn the power off and on again, and check if all the EVs generate a latching sound.

3. If any of the EVs does not generate a latching sound in the above step 2, disconnect that connector and check the continuity using a multimeter.

Check the continuity between the pins 5 - 1, 5 - 2, 5 - 3, 5 - 4. If there is no continuity between the pins, the EV coil is faulty.

4. If no EV generates a latching sound in the above step 2, the outdoor unit PCB is faulty.

5. If the continuity is confirmed in the above step 3, mount a good coil (which generated a latching sound) in the EV unit that did not generate a latching sound, and check if that EV generates a latching sound.

∗If a latching sound is generated, the outdoor unit PCB is faulty.

∗If a latching sound is not generated, the EV unit is faulty.

Warning: Ensure the voltage between (+) and (-) of the power module is about 0 V before proceeding

Enter the voltage between (+) and (-) of the power module

Disconnect the compressor harness connector from the outdoor unit PCB. To disengage the connector, press the protrusion on the connector.

Was the compressor harness connector successfully disconnected?

Measure resistance between the (+) or (-) terminal of the power module and the U, V or W terminal of the compressor with a multimeter.

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module check

Make sure that the voltage of 320 V is applied.

Set operation off and power off. Disconnect the connector S70.

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

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

Check that the rotation command voltage between the pins 4 - 2 is 0 ~ 15 VDC.

Keep operation off and power off. Connect the connector S70.

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

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

CTXG, FTXR, CTXS, FTXS, FVXS Series

1. Check the connection of connector.

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

3. Check motor control voltage (pins 4 - 3).

4. Check rotation command voltage output (pins 4 - 2).

5. Check rotation pulse input (pins 4 - 1).

2. With the fan motor connector disconnected, measure the resistance between each pin, then make sure that the resistance is more than the value mentioned in the following table.

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

Thermistors disconnected from the PCB?

Measure the resistance of each thermistor using a multimeter

Note: The data is for reference purpose only.

Is the room temperature thermistor soldered on a PCB?

If yes, remove the PCB from the control PCB to measure the resistance.

Is the connector of indoor heat exchanger thermistor soldered on a PCB?

If yes, remove the thermistor and measure the resistance.

Sign off on the thermistor resistance check