Fault Code Lookup

HVAC Sales Master
E252
Discharge air temperature too high (gas heat only)
This code typically points to
  • High temperature rise
  • Airflow issue
  • Excess input rate

Next checks to confirm
  1. Check temperature rise
  2. Check airflow
  3. Check input rate

Escalation
Heat protection alert
Reset behavior
Clears when heat call is finished.
Urgent
Fix now
Source
Lennox unit information doc 100027, p.13