Daikin Cooling-Only Outdoor Unit For SkyAir System RZR42TAVJUA

Warning: This procedure requires trained personnel with PPE!

Enter the superheating degree of suction gas

Is the compressor discharge gas temperature higher?

Does the electronic expansion valve turn open?

Does low pressure drop causing the unit not to demonstrate cooling capacity (heating capacity)?

Sign off on the refrigerant shortage check

Warning: This procedure requires trained personnel with PPE!

Enter the high pressure reading

Is the high pressure causing insufficient cooling capacity?

Enter the superheating degree of suction gas

Is the compressor lower in discharge pipe temperature despite of pressure loads?

Enter the subcooling degree of condensate

In heating, is the temperature of discharge air through the subcooled section lower?

Sign off on the refrigerant overcharge check

Warning: Ensure the power supply to all equipment is turned OFF before starting the procedure.

Power supply to all equipment turned OFF

Short circuit between the indoor-outdoor unit terminal F1 and F2 in the outdoor unit.

Short circuit between the indoor-outdoor unit terminal F1 and F2 in the outdoor unit completed

Continuity checks between the transmission wirings F1 and F2 of the 'Indoor Unit a'

Continuity between the transmission wirings F1 and F2 of the 'Indoor Unit a'

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

With the indoor-outdoor unit terminal of the outdoor unit short circuited, identify the place with continuity in the transmission wiring of the 'Indoor Unit b', 'Indoor Unit c', and 'Indoor Unit d' in the order described.

Continuity in the transmission wiring of the 'Indoor Unit b'

Perform the following procedures prior to check.

(2) Remove all the wiring connected to the PCB where power transistors are mounted on.

Preparing a multimeter in the analog system is recommended.

A multimeter in the digital system with diode check function will be usable.

[Point of Measurement and Judgment Criteria]

· Measure the resistance value using a tester at each point of measurement below, 10 minutes later after power OFF.

Conduct vacuuming and dehydration in the piping system following the procedure for Normal vacuuming and dehydration described below.

Furthermore, if moisture may get mixed in the piping system, follow the procedure for Special vacuuming and dehydration described below.

Normal vacuuming and dehydration

Use a vacuum pump that enables vacuuming up to 500 microns.

Connect manifold gauges to the service ports of liquid pipe and gas pipe and run the vacuum pump for a period of 2 or more hours to conduct evacuation to 500 microns.

If the degree of vacuum does not reach 500 microns or less even though evacuation is conducted for a period of 2 hours, moisture will have entered the system or refrigerant leakage will have been caused. In this case, conduct evacuation for a period of another 1 hour.

If the degree of vacuum does not reach 500 microns or less even though evacuation is conducted for a period of 3 hours, conduct the leak tests.