FieldBench
Lennox codes

Lennox

E250 / 4-flash

Protect

Limit

Airflow / overtemp. 5-flash on a flash SKU is still rollout.

Walk E250 / 4-flash in Diagnose

Sign in for the next measurement

First check

1 Treat this as flame outside the exchanger

Do not reset the Lennox SL280 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 or heat tap, filter, coil. Rollout: exchanger and metal flue.

Plates that use E250 / 4-flash