McQuay M5MSY18BR User Manual

46
M5MSY_(i) Troubleshooting
Error
Codes
Error Description Action
E3 High pressure protection
1. Check installation conditions.
2. Check stop valve.
3. Check HPS connection.
4. Check pressure level by pressure gauge.
5. Wait for 10 minutes then restart the system.
6. Check if H3 is displayed.
E4 Low pressure protection
1. Check stop valve.
2. Check low pressure sensor connection.
3. Check low side pressure and voltage.
4. Check outdoor coil sensor connection.
5. Check sensor resistance value.
6. Check refrigerant level.
E5 Compressor motor lock/overload
1. Check connection on discharge pipe sensor.
2. Check discharge pipe sensor resistance value.
3. Check the EXV.
4. Check the refrigerant line on blockage or shortage.
E6 Compressor lock/start-up error
1. Check with inverter checker.
2. Check the EXV.
E7 Outdoor DC fan motor lock
1. Check the fan motor connection.
2. Check if foreign matters exist around or in the fan.
E8 Ac input over current
1. Measure the input current.
2. Check the main circuit electrolytic capacitor.
3. Check with inverter checker.
4. Check discharge pressure.
5. Check the installation condition.
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 abnor-
mality
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.

McQuay M5MSY18BR Specifications

General

Brand	McQuay
Model	M5MSY18BR
Category	Air Conditioner
Language	English