Daikin VRV X Series Standard Type Air Conditioner RXQ8ARY1

CHECK 4: Perform the following procedures prior to check.

Remove all the wiring connected to the PCB where power transistors are mounted on

Point of Measurement and Judgment Criteria

Then, after a lapse of 10 minutes or more, make measurement of resistance.

Enter the resistance measurement in the x1 k range

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 central remote controller using a multimeter

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'

Warning: This test operation requires trained personnel with PPE!

INFORMATION: It may take 10 minutes to achieve a uniform refrigerant state before the compressor starts.

During the test operation, the refrigerant running sound or the magnetic sound of a solenoid valve may become loud and the display indication may change. These are not malfunctions.

All front panels are closed (except the electrical component box inspection opening service cover)?

NOTICE: Be sure to turn on the power 6 hours before operation in order to protect the compressor

Is the power to the outdoor unit and the connected indoor units turned ON?

Is the default (idle) situation existing?

Push BS2 for 5 seconds or more. The unit will start test operation.

Resistance between phases of U, V, W at the motor side connectors

Values are balanced and there is no short circuiting

Resistance between the U and V, V and W, and W and U phases of the motor connector

Each phase are balanced (within a permissible dispersion range of ±20%)

Fan Motor Connector Check (Signal Cable)

CHECK 6 In case of VRV systems, the only way to judge as the overcharge of refrigerant is with operating conditions due to the relationship to pressure control and electronic expansion valve control.

As information for making a judgment, refer to the information below.

Diagnosis of refrigerant overcharge

1. High pressure rises. Consequently, overload control is conducted to cause insufficient cooling capacity.

2. The superheating degree of suction gas lowers (or wet operation is performed).

Consequently, the compressor becomes lower in discharge pipe temperature despite of pressure loads.

3. The subcooling degree of condensate rises.;