FieldBench
Lennox codes

Lennox

E312

Protect

Restricted airflow — cooling / CF

Cooling or continuous-fan CFM is below the setting. Cutback / high-static warning.

Walk E312 in Diagnose

2 plates — walk the one on the cabinet

First check

1 Airflow before you touch the limit

On Lennox EL195NE a limit is airflow or overfire until proven otherwise. Do not replace the limit first. Filter, blower wheel, A-coil, and the heat-speed setting for THIS motor (tap, model plug, or communicating CFM — not a sister SKU chart). Filter and duct. VS motor is already in torque limit (roughly 0–0.8 in. w.c. class).

Expect: Rise in the rating-plate window. Static vs this cabinet’s blower chart.

The rest of the walkthrough is Diagnose.

On the plates

  • Filter and duct. VS motor is already in torque limit (roughly 0–0.8 in. w.c. class).
  • Not a heat-call code. Do not chase E312 with a pressure switch.

Plates that use E312