FieldBench
Lennox codes

Lennox

E250

Protect

Limit switch circuit open

Limit / rollout string open. Open >3 min → E274.

Walk E250 in Diagnose

6 plates — walk the one on the cabinet

First check

1 Treat this as flame outside the exchanger

Do not reset the Lennox EL195NE rollout and walk away. Write the code, kill the call, and look for flame at the burners, crossover, and vestibule before you do anything else.

Expect: No flame outside the exchanger. Burners seated. Crossover lit.

If pass: Still inspect secondary / flue / condensate before you reset.

The rest of the walkthrough is Diagnose.

On the plates

  • VS heat CFM vs the EL296 chart — not a 9-speed tap. Filter, coil, media cabinet.
  • Walk the rollout string if E270 / E274 also store. Manual-reset rollout is a hazard until the cause is gone.
  • Heat tap vs rise — this is a CT motor, not VS CFM.
  • Media cabinet, coil, filter. Rollout if E274 stores.
  • Heat CFM follows %. Filter, coil, rise. Rollout is still manual reset.

Plates that use E250