Fault Code Lookup

HVAC Sales Master
E180
Outdoor air temperature sensor failure
This code typically points to
  • Sensor shorted or out of range

Next checks to confirm
  1. Compare sensor resistance to Lennox temperature/resistance chart
  2. Replace sensor pack if needed
  3. Reconfigure if feature should be marked not installed

Escalation
Sensor-based feature fault
Reset behavior
Clears 30 seconds after recovery.
Service Soon
Schedule repair
Source
Lennox unit information doc 100027, p.11