HVACopedia

Lennox · Heat pump

610 Low room temperature detected

High severity

What the control is telling you

Indoor temp fell under the freeze alert set point (adjustable 30 F to 50 F, or -1.11 C to 10.0 C; factory 40 F / 4.44 C). Owner and dealer get a notice if Wi-Fi and a valid email are set up. S30/S40 alert code 610.

Applies to: Lennox communicating heat pumps incl. variable-capacity inverter units in S30/S40 smart thermostat systems

Likely causes

  • No heat
  • Set point/alert setting

Test and repair steps

  1. Check why the system is not heating (other alert codes).
  2. Clears when resolved.

Settings for these units

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Source: Lennox Residential Communicating Systems Alert Code Guide (V2) 100017 (3/2023), Table 2 Alert Codes and Troubleshooting, p.46. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

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.