McQuay M5CKY28ER User Manual

Troubleshooting M5LCY-II_(i)
50
Error Codes Error Description Action
E9 EXV error
1. Restart the system.
2. Check the EXV connection.
3. Check EXV coil resistance.
4. Check sensors resistance value.
EA 4-way valve error
1. Check 4WV coil connection.
2. Check the continuity of the 4WV coil and harness.
3. Check the 4WV switching output.
4. Check sensor connection.
5. Check sensor resistance value.
6. Check the refrigerant line on blockage or
shortage.
F3 Discharge pipe overheat
1. Check the discharge pipe sensor.
2. Check the EXV.
3. Check the refrigerant line on blockage or
shortage.
F6 Heat exchanger overheat
1. Check the installation space.
2. Check the outdoor fan.
3. Check the EXV.
4. Check the coil sensor.
H0
Compressor sensor system
abnormality
1. Check the reactor connection.
2. Check the compressor connection.
3. Measure the resistance value between the reactor
terminals.
4. Measure the resistance value between the
compressor terminals.
H3 High pressure switch error
1. Check pressure sensor connection.
2. Check HPS continuity.
H6 Position sensor abnormality
1. Check for short circuit.
2. Check the electrolytic capacitor voltage.
3. Check compressor harness wire.
4. Check with inverter checker.
H8 AC current sensor error
1. Restart the system.
2. Check capacitor voltage.
3. Measure the rectifi er input voltage.
4. Check compressor harness wire.
5. Check with inverter checker.
H9 Outdoor air thermistor short / open
1. Check the sensor connection.
2. Check the sensor resistance value.
J1 Pressure sensor error
1. Check pressure sensor connection.
2. Check pressure and voltage level.
J3
Compressor discharge pipe
thermistor short / open / misplaced
1. Check the sensor connection.
2. Check the sensor resistance value.
3. Check indoor coil sensor resistance value.

McQuay M5CKY28ER Specifications

General

Brand	McQuay
Model	M5CKY28ER
Category	Air Conditioner
Language	English