Lennox 71G12 Rollout Switch

The Lennox 71G12 Rollout Switch is a critical safety component designed for precise thermal monitoring in residential gas furnaces. Engineered with a fixed set point of 210°F, this SPST (Single Pole Single Throw) manual reset limit switch serves as the primary line of defense against flame rollout, which occurs when flue gases or flames bypass the heat exchanger due to restricted venting, cracked heat exchangers, or low manifold pressure. This genuine Lennox OEM replacement is electrically identical to the 36TX16-6013 and is required for maintaining the safety sequence of the furnace control board by breaking the 24V circuit to the gas valve upon detecting unsafe ambient temperatures in the burner compartment.

For technicians servicing Lennox G23, G26, and G12 furnace series, this switch provides an exact fit without the need for mounting modifications. Because it is a manual reset rollout switch, a trip indicates an underlying equipment failure that must be diagnosed—such as a blocked flue or a compromised primary heat exchanger—before the system is returned to service. Using official Lennox furnace parts ensures that the safety timings and temperature curves remain within the original manufacturer's design parameters for reliable combustion safety.

• High-Precision Calibration: Set to trigger at 210 degrees Fahrenheit to prevent damage to internal furnace components.
• OEM Compatibility: Drops directly into existing brackets for Lennox 71G12 and 36TX16-6013 applications.
• Professional Grade Safety: Features a manual reset button, forcing a manual inspection of the heat exchanger and venting after any high-limit event.
• Durable SPST Logic: Provides a clean break in the safety loop for immediate system shutdown during flame rollout conditions.

Common Questions

What causes a Lennox rollout switch to trip?
A trip is typically caused by a restricted exhaust vent, a cracked heat exchanger, soot buildup on the burner faces, or low gas pressure preventing the flame from being properly pulled into the heat exchanger tubes.

Can I replace the 36TX16-6013 with the 71G12?
Yes, the 71G12 is the direct genuine OEM replacement for the 36TX16-6013, sharing identical 210F temperature ratings and SPST electrical characteristics.

Is it safe to reset this switch and continue operation?
A rollout switch trip is a major safety event. A veteran technician must inspect the furnace for heat exchanger integrity and venting obstructions before resetting the device to ensure there is no risk of carbon monoxide leakage or fire.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.