16 Troubleshooting - electrical LED error indicatorsError codes
17 Troubleshooting - electrical Room sensor contact open/shortBlink 1 timeSensor RTH201Possibility – lowUnit design with air opening at the front panel to allow sufficient space for air flow & measurement10 C < operating temp. < 40 CError codes
18 Troubleshooting - electrical ID coil sensor open/shortBlink 2 times Blinking- 10 C < operating temp. < 68 CError codes
23 Troubleshooting- mechanical Charging refrigerantLP valve close, HP valve openLP valve open, HP valve close
24 Troubleshooting - mechanical Vacuuming Method1) Open the service port core cap.2) Connect pressure gauge to the service port.3) Connect the line to vacuum pump. Open the charging manifold valve and turn the pump on.Vacuum to –0.1 MPa (-760mmHg) or lower. (Evacuation time varies by the pump but averagely in 1 hour).Refrigerant circuit checks
25 Troubleshooting- mechanical Vacuum pumpingValve open
26 Troubleshooting-mechanical Compressor OverloadLED display Blink 1 time(Cooling)When OD coil temperature > 68 °C, both the compressor and outdoor fan will stop operating.(Heating)When ID coil temperature > 68 °C, the compressor, outdoor fan and 4 way valve will stop operating.
27 Troubleshooting-mechanical Measure ID/OD on coil temperature > 68°C ?YESNONOSufficient airflow?Ensure no obstacle around the unit and conduct inspection on coil and filter.YESNOIs the coil sensor correctly connected?Connect correctly and operate again.YESNOIs the coil sensor resistance characteristics normal?Replace sensor.YESNONOMeasure compressorwinding resistance. Within spec ?2.5 – 4 Ampere?Measure comp running amp. Within spec?Change compressor.Is compressor short body?NOCompressor OKYESYESChange compressor.NOSuction = psigDischarge = psigUnit overcharged. Recover all gas.Measure suction pressure. Within spec?YESRecharging with correct amount of refrigerant.System ok.
28 Troubleshooting-mechanical Gas LeakLED display Blink 3 timesAfter compressor’s run time of 30 minutes is achieved, gas leak is declared if:ID coil temperature > 25°C (cooling) or < 20°C ( heating )
29 Troubleshooting-mechanical Turn on the unitNOIs the coil sensor correctly connected?Connect correctly and operate again.YESNOIs the coil sensor resistance characteristics normal?Replace sensor.YESNONOMeasure compressorwinding resistance. Within spec ?Measure compressor running ampere. Within spec?Change compressor.2.5 – 4 Ampere?Is compressor short body?NOCompressor OKYESYESChange compressor.NONOSuction = psigDischarge = psigMeasure suction pressure. Within spec?Detect the leak point?Refer to leak detection method.YESYESFix the leak point.System ok.
30 Troubleshooting- mechanical Hardware Error (tact switch pin open)LED display Blink 6 timesPossible root cause:ON/OFF tact switch accidentally pressed by front cover and could not restore back to normal position.
31 Troubleshooting- mechanical Visual inspection on the ON/OFF.NOON/OFF pressed by cover?YESPress once on the ON/OFFbutton for 1 second.
32 Troubleshooting- mechanical No feedback from indoor fan motorLED display OFF Blink 4 timesPossible root cause:Incorrect fan motor wire connection / defective fan motor.
33 Troubleshooting- mechanical NOCheck fan motor wire connection. Correct?Reconnect in correct position.`YESCheck fan motor and replace with another motor.