OEM Service Manual: Lennox TCS Water-Cooled Screw Chiller Service Manual. Available through Lennox Commercial technical support.
30 codes
| Fault Code | Alarm Description | Severity | Probable Causes | Action |
|---|---|---|---|---|
| E01 | High pressure alarm | Critical | Condenser water flow insufficient | View Details → |
| E02 | Low pressure alarm | Warning | Low refrigerant charge | View Details → |
| E03 | Compressor motor overload | Critical | Motor bearing failure | View Details → |
| E04 | Discharge temperature high | Warning | High compression ratio | View Details → |
| E05 | Evaporator water flow fault | Warning | Pump stopped or failed | View Details → |
| E06 | Condenser water flow fault | Warning | Condenser pump stopped | View Details → |
| E07 | Evaporator freeze protection | Critical | Water temperature near freezing | View Details → |
| E08 | Sensor fault | Warning | Sensor element failure | View Details → |
| E09 | Communication fault | Warning | Network cable fault | View Details → |
| E10 | Phase fault | Warning | Phase loss | View Details → |
| E11 | Oil pressure low | Critical | Oil pump wear | View Details → |
| E12 | Oil level low | Critical | Refrigerant leak carrying oil | View Details → |
| E13 | Expansion valve fault | Warning | Valve motor failure | View Details → |
| E14 | Power supply fault | Warning | Voltage outside specification | View Details → |
| E15 | Fan motor fault | Warning | Motor winding failure | View Details → |
| E16 | Fan motor fault | Warning | Fan motor winding failure | View Details → |
| E17 | Compressor 2 fault | Warning | Compressor 2 motor overload | View Details → |
| E18 | Compressor 2 high pressure | Critical | Condenser 2 fouled | View Details → |
| E19 | Compressor 2 low pressure | Warning | Low refrigerant on circuit 2 | View Details → |
| E20 | Compressor 2 discharge temperature high | Warning | Compression ratio too high on circuit 2 | View Details → |
| E21 | Compressor 2 oil pressure low | Critical | Oil pump 2 failure | View Details → |
| E22 | Crankcase heater fault | Warning | Crankcase heater element failure | View Details → |
| E23 | Liquid line solenoid fault | Warning | Solenoid coil failure | View Details → |
| E24 | Hot gas bypass fault | Warning | Hot gas bypass valve actuator failure | View Details → |
| E25 | Pumpdown sequence fault | Warning | Pumpdown solenoid not closing | View Details → |
| E26 | Compressor vibration alarm 2 | Warning | Compressor 2 mounting bolts loose | View Details → |
| E27 | Remote panel fault | Warning | Remote panel communication cable damaged | View Details → |
| E28 | Surge detection 2 | Warning | Compressor 2 operating near surge line | View Details → |
| E29 | Subcooling low alarm 2 | Warning | Refrigerant charge low on circuit 2 | View Details → |
| E30 | Superheat alarm 2 | Warning | Expansion valve 2 starving | View Details → |
Disclaimer: All Lennox TCS 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.