Daikin Cassette Type Indoor Unit FDBT42NUV2S

Warning: Disconnect the thermistor from the PCB before proceeding

Thermistor disconnected from the PCB

Upload a photo of the table with the measured values

Do the measured values correspond with the values in the table?

Sign off on the thermistor check

Check for Fan Motor Connector (Signal Line)

(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.

(2) With the fan motor connector disconnected, measure the resistance between each pin, then make sure that the resistance is balanced in ±30%.

Check for Fan Motor Connector (Power Supply Line)

With the relay connector disconnected, measure the resistance between UVW phases of the connector (3 cores) at the motor side, then make sure that the resistance between each phase is balanced and not short-circuited.;

Procedure for checking outdoor-outdoor unit transmission wiring for broken wires

Turn OFF the power supply to all equipment

Short circuit between the outdoor-outdoor unit terminal F1 and F2 in the 'Outdoor Unit A'

Conduct continuity checks between the transmission wiring terminal blocks F1 and F2 of the centralized remote controller using a multiple meter

Is there continuity between the said terminal blocks?

If there is no continuity, the transmission wiring may have broken wires

Conduct continuity checks between the transmission wiring terminal blocks F1 and F2 of the unified ON/OFF controller

Conduct continuity checks between the outdoor-outdoor unit terminal of the 'Outdoor Unit E'

Conduct continuity checks between the outdoor-outdoor unit terminal of the 'Outdoor Unit D'

Set operation OFF and power OFF. Disconnect the connector.

Keep operation OFF and power OFF. Connect the connector.

2 pulses (0 and 5 VDC) are output 4 times at the pins 1 - 4 when the fan motor is rotated 1 turn by hand.

Sign off on the fan motor pulse check

As criteria for judging whether refrigerant is excessively charged or not, refer to the following operating conditions.

<Diagnosis of excessive refrigerant charging>

(1) Because high pressure rises due to excessive charging, overload control is carried out and capacity tends to run short.

(2) Considering pressure load, compressor discharge pipe temperature is low.

(3) Subcooling degree of condensate liquid becomes large. Therefore, temperature of blown air passing through subcooling part decreases in heating operation.;