OEM Lennox Flame Rollout Switch — 71W49

The genuine OEM Lennox 71W49 flame rollout switch is a manual-reset safety limit that guards against flames escaping the combustion chamber or burner box in your Lennox furnace. If temperatures near the burners exceed a safe threshold — a sign of flame rollout — the switch trips and cuts power to the gas valve, shutting the furnace down to prevent damage and hazard.

When this switch trips or fails, the furnace will typically stop heating and lock out. Repeated tripping is usually a warning sign of an underlying problem such as a cracked heat exchanger, blocked flue, dirty burners, or a failing inducer, so the root cause should always be investigated rather than simply resetting or bypassing the switch.

Installing the OEM Lennox 71W49 ensures the correct trip temperature, reset behavior, and mounting fit that Lennox engineered for this safety circuit. A generic switch with a different setpoint can either nuisance-trip or, worse, fail to protect against a genuine rollout condition. Never defeat this safety — replace with the factory-matched part and have the cause of any trip diagnosed by a professional.