Daikin Outdoor Unit For Reverse Cycle System RY160LUY1

Temperature differences must occur before or after the clogged points!

Replace the electronic expansion valve.

Blow a nitrogen gas, and then replace the refrigerant.

Replace the heat exchanger or distributor.

Collapsed pipe Replace the pipe.

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

<Diagnosis of inadequate refrigerant>

(1) As suction superheated degree increases due to refrigerant shortage, the electronic expansion valve tends to open (opens fully) in order to avoid overheat operation.

(2) In response to decreased evaporator capacity caused by refrigerant shortage, capacity is controlled in the inverter in order to maintain low pressure, which results in a decrease in frequency.

(3) Because of (1) and (2) above, the compressor frequency decreases despite a large difference (large load) between temperature set by the remote controller and suction air temperature, resulting that cooling capacity becomes unavailable.

(4) If refrigerant shortage worsens, the electronic expansion valve remains fully open and suction superheated degree further increases. In addition, as compressor frequency drops to the level of the lowest frequency (41 Hz), low pressure cannot be maintained

<Diagnosis of inadequate refrigerant>

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

Power supply to all equipment turned OFF?

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

Continuity checks between the transmission wiring terminal blocks F1 and F2 of the centralized remote controller

Continuity between the said terminal blocks?

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

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

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

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

Warning: Do not touch the energized part (high voltage part) for at least 10 minutes after the power is turned OFF.

Be sure to touch the earth terminal with a hand to release static electricity from the body (to prevent PCB from being damaged).

Residual electric charge of the power transistor (should be DC 50V or less)

Remove the connector of the outdoor unit fan motor.

Remove the wire connecting the power transistor and the compressor. Remove it from the compressor terminal side.

During this work, be careful not to deform. Faston terminal at the end of the relay wire.

Resistance measurement for phase 1

Resistance measurement for phase 2

Warning: Disconnect the thermistor from the PCB before proceeding

Thermistor disconnected from the PCB

Temperature reading from the thermistor

Resistor value from the thermistor

Check if the measured values correspond with the values in the table

Sign off on the thermistor check