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69

Malfunction Decision Conditions
During operation of cooling and heating, when compressor tank temperature data (112°C) is detected by the compressor
tank temperature sensor.

• Refrigerant shortage (refrigerant leakage).
• 2/3 way valve closed.
• Detection error due to faulty compressor tank temperature sensor.

70

Malfunction Decision Conditions
During operation of cooling and heating, when an input over-current (15.06A) is detected by checking the input current value
being detected by current transformer (CT) with the compressor running.

• Over-current due to compressor failure.
• Over-current due to defective outdoor unit PCB.
• Over-current due to defective inverter main circuit electrolytic capacitor.
• Over-current due to excessive refrigerant.

71

Malfunction Decision Conditions
During operation of cooling and heating, when an output over-current (20.2A) is detected by checking the current that flows in the
inverter DC peak sensing circuitry.

• DC peak due to compressor failure.
• DC peak due to defective power transistor(s).
• DC peak due to defective outdoor unit PCB.

• Checking the power transistor.
• Never touch any live parts for at least 10 minutes after turning off the circuit breaker.
• If unavoidable necessary to touch a live part, make sure the power transistor’s supply voltage is below 50V using the tester.
• For the UVW, make measurement at the Faston terminal on the board of the relay connector.

72

1. Open the Intake Grille from the Front Grille by moving the

catchers to center (Fig.1).

2. Remove the Control Board Cover by removing the screws

(Fig. 2).

3. Release the  (Fig. 3):

• CN-STM1 (WHT) connector.
• CN-STM2 (YLW) connector.
• CN-DISP (WHT) connector.
• CN-FM (WHT) connector.
• CN-TH1 (WHT) connector.
• CN-TH2 (BLU) connector.
• CN-DRMTR1 (BLU) connector.
• AC01 (BLK), AC02 (WHT) and CN-DRMTR2 (RED) from

Terminal Board.

• G01 (GRN) screw.
• Two T-BLK connectors.
• CN-T1 (WHT).
• CN-T2 (YLW).

Fig. 1

Fig. 2

Fig. 3

High Voltage are generated in the electrical parts area by the capacitor. Ensure that the capacitor has discharged sufficiently before proceeding
with repair work. Failure to heed tis caution may result in electric shocks.