OEM Service Manual: McQuay MCS Modular Chiller Service Manual. Available through Daikin Applied technical support.
30 codes
| Fault Code | Alarm Description | Severity | Probable Causes | Action |
|---|---|---|---|---|
| E01 | Module 1 compressor high pressure | Critical | Module 1 condenser fouled | View Details → |
| E02 | Module 1 compressor low pressure | Warning | Low refrigerant in module 1 | View Details → |
| E03 | Module 2 compressor fault | Warning | Module 2 compressor overload | View Details → |
| E04 | Module 3 compressor fault | Warning | Module 3 compressor overload | View Details → |
| E05 | Module communication fault | Warning | Inter-module communication cable damaged | View Details → |
| E06 | Common evaporator water flow fault | Warning | Chilled water pump stopped | View Details → |
| E07 | Module isolation valve fault | Warning | Isolation valve motor failure | View Details → |
| E08 | Capacity control fault | Warning | Capacity staging logic error | View Details → |
| E09 | Sensor fault | Warning | Sensor element failure | View Details → |
| E10 | Phase fault | Warning | Phase loss | View Details → |
| E11 | Oil pressure fault | Warning | Oil pump wear | View Details → |
| E12 | Power supply fault | Warning | Voltage outside spec | View Details → |
| E13 | Freeze protection | Critical | Evaporator water temp near freezing | View Details → |
| E14 | Expansion valve fault | Warning | Valve motor failure | View Details → |
| E15 | Fan motor fault | Warning | Motor winding failure | View Details → |
| E16 | Condenser water temperature high | Warning | Cooling tower issue | View Details → |
| E17 | Condenser fan 2 fault | Warning | Fan 2 motor failure | View Details → |
| E18 | Compressor vibration alarm | Warning | Mounting loose | View Details → |
| E19 | Pumpdown failure | Warning | Solenoid not closing | View Details → |
| E20 | Compressor surge alarm | Warning | Near surge line | View Details → |
| E21 | High bearing temperature | Warning | Lubrication inadequate | View Details → |
| E22 | Low subcooling alarm | Warning | Charge low | View Details → |
| E23 | High superheat alarm | Warning | Valve starving | View Details → |
| E24 | Compressor start inhibit | Warning | Safety interlock preventing start | View Details → |
| E25 | Evaporator approach temperature high | Warning | Fouled tubes | View Details → |
| E26 | Condenser approach temperature high | Warning | Fouled condenser | View Details → |
| E27 | Energy efficiency alarm | Warning | Below expected efficiency | View Details → |
| E28 | Compressor runtime exceeded | Warning | Exceeded max runtime | View Details → |
| E29 | Refrigerant level alarm | Warning | Level sensor low | View Details → |
| E30 | Cooling tower water fault | Warning | Tower fan not operating | View Details → |
Disclaimer: All McQuay MCS fault code data is for reference only. Do not use this information to replace certified professional HVAC technician judgment. Always refer to original OEM official service manual.