Lennox 15M42 Rollout Switch

Maintain critical furnace safety and prevent equipment damage with the Lennox 15M42 Rollout Switch. Designed as a direct-fit OEM replacement flame rollout switch, this component is engineered to monitor the burner compartment for abnormal heat conditions. The 15M42 is a single-pole single-throw (SPST) switch calibrated to actuate at 250 degrees F, effectively interrupting the burner circuit if a flame rollout or excessive thermal event occurs. This model is technically identical to the Lennox 15M4201, ensuring seamless integration into existing Lennox HVAC systems, including LGA and LGC series commercial units as well as residential gas furnaces.

As a manual reset rollout switch, this device requires physical technician intervention after a trip, preventing the system from automatically restarting until the root cause of the rollout is identified and resolved. This furnace safety limit switch features a distinct red identification color for rapid diagnosis during service calls. Utilizing genuine Lennox parts ensures precise electrical ratings and thermal response times that meet the rigorous specifications managed by HVAC flame rollout protection standards.

• Universal Compatibility: Replaces 97J68, 97J6801, and 15M4201 across diverse Lennox and Allied models.
• High-Precision Actuation: Operates exactly at 250°F with a +/- 12°F tolerance for consistent system protection.
• Manual Reset Safety: Prevents unsafe automatic cycling of the unit following a safety lockout.
• Heavy-Duty Construction: Built for high-ambient burner environments to ensure long-term thermal stability.

What causes a 250F rollout switch to trip?
A trip usually indicates a blockage in the heat exchanger, poor drafting in the flue, or gas pressure issues causing the flame to "roll out" of the combustion chamber.

Is the 15M42 interchangeable with the 15M4201?
Yes, the 15M42 and 15M4201 are numerically and technically identical parts with the same SPST configuration and 250F limit.

How do I reset this switch?
Once the temperature drops below the trip point, the small red button on the back of the bracket can be depressed to restore the circuit.

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.