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09:41
Lennox locking out — code E227. What's it telling me?
09:41
E227 — low-pressure switch opened during trial for ignition Got your unit from the nameplate: SL280DFNV series. The switch closed, then dropped out mid-ignition — different fault than E223 (never closed). Check: 1. Inducer pressure (in. w.c.) against the switch rating 2. Pressure/condensate tubing — blocked, kinked or iced 3. Flue restriction before condemning the switch

Source: Lennox SL280DFNV installation & operation manual

09:41
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Job 013 — Gas furnace, no heatLennox SLP99UHV
E227

Soft lockout — retrying ignition

Inducerrunning

Pressure switchopened during trial

What's your move?

Condemn the pressure switch
Check inducer draft & tubing first+150 PTS
Replace the control board

Technician verified — from the OEM service manual

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