Daikin Outdoor Heat Pump RXL09QMVJU

Warning: This check requires trained personnel with PPE!

Enter the power supply waveform measurement between No. 1 and No. 2 on the terminal strip

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)?

Upload a photo of the measured waveform

Sign off on the power supply waveform check

EV connector correctly connected to the PCB

Did the EV generate a latching sound after power cycle

Continuity confirmed using a multimeter after disconnecting the connector

Check the continuity between the pins

Outdoor unit PCB (main PCB) is not faulty

Sign off on the electronic expansion valve check

If an abnormal stop occurs due to compressor startup failure or overcurrent output when using an inverter unit, it is difficult to judge whether the stop is caused by the compressor failure or some other failure (main PCB, power module, etc.). The inverter analyzer makes it possible to judge the cause of trouble easily and securely. Connect an inverter analyzer as a quasi-compressor instead of compressor and check the output of the inverter.

Step 1: Be sure to turn the power off.

Step 2: Install an inverter analyzer instead of a compressor.

Note: Make sure the charged voltage of the built-in smoothing electrolytic capacitor drops to 10 VDC or below before carrying out the service work.

(1) Remove the terminals from the compressor.

(2) Connect the terminals to the terminals of the inverter analyzer.

Warning: Disconnect the connector of thermistor ASSY from the PCB before proceeding

Enter the resistance value measured from the thermistor

Does the measured resistance value match the listed value?

If the measured resistance value does not match the listed value, the thermistor must be replaced.

To check the thermistor soldered on a PCB, disconnect the PCB from other PCB/parts

Enter the resistance value measured from the soldered thermistor

Does the measured resistance value match the listed value?

If the measured resistance value does not match the listed value, the thermistor must be replaced.

Sign off on the thermistor resistance check

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

Voltage between (+) and (–) of the power module is about 0 V

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

Compressor harness connector disconnected

Measure resistance between the terminals of the power module and the terminals of the compressor with a multimeter

Enter the resistance measurement

Evaluate the measurement results

Sign off on the power module check