Lennox · Air conditioner
E414 High discharge line temperature
What the control is telling you
Discharge line temperature is above the 279 F limit. S30/S40 thermostat alert code 414 (shown as E414 on the unit control display).
Applies to: Lennox communicating air conditioners incl. variable-capacity inverter units in S30/S40 smart thermostat systems
Likely causes
- Dirty coil or blocked airflow
- Low charge / high superheat
- Abnormal operating pressures
Test and repair steps
- Clean the coil and clear airflow in and out of the condenser.
- Check pressures against the unit charging charts.
- Clears when discharge temperature drops below 225 F.
Settings for these units
- Outdoor unit clearances · Lennox EL16KC1
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Source: Lennox Residential Communicating Systems Alert Code Guide (V2) 100017 (3/2023), Table 2 Alert Codes and Troubleshooting, p.30. Summarized in our own words; check the original manual for your model.
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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.