Lennox codes

Lennox

E223 / 3-flash

Lockout

Low PS open / draft

Low-fire prove failed. On this 80% that is chimney, inducer, common vent — not a drowned 96% trap.

Walk E223 / 3-flash in Diagnose

Sign in for the next measurement

First check

1 Prove inducer and the live code

Do not pull power — that clears the Lennox SL280 active code. Write E223 / 3-flash. Is the inducer spinning on this call? Silent inducer is not a pressure switch. Metal vent, liner, common-vent sizing, inducer wheel, burner-box intake.

Expect: 120 VAC at the inducer on a heat call. Wheel turning.

If fail: 120 VAC missing → IFC / door switch / incoming power. Voltage + dead motor → inducer.

If pass: Inducer running + this code → trap, hose, switch, vent (step 2).

The rest of the walkthrough is Diagnose.

On the plates

  • Metal vent, liner, common-vent sizing, inducer wheel, burner-box intake.
  • If the display is E223 you are on a SureLight VS SKU. Same number as EL296V, opposite vent physics.

Plates that use E223 / 3-flash