OEM Lennox Flame Rollout Limit Switch — 98M86

The genuine OEM Lennox 98M86 flame rollout switch is a manual-reset safety limit that protects your Lennox furnace from dangerous overheating conditions. Mounted near the burner assembly, it monitors for flame rollout — a condition where flames escape the combustion chamber, typically caused by a blocked heat exchanger, restricted flue, or failing inducer. If it senses excessive heat, it instantly interrupts power to the gas valve, shutting the furnace down before damage or a hazard can occur.

Common failure symptoms: A tripped or failed rollout switch will cause the furnace to stop producing heat entirely. You may find the furnace lighting briefly then shutting off, a switch that won't reset, or repeated lockouts. Because this switch responds to an underlying combustion or airflow problem, a persistent trip should always prompt inspection of the heat exchanger and venting.

Why OEM matters: This is a safety-critical component with a factory-specified trip temperature. The OEM 98M86 is calibrated to your Lennox furnace's exact design limits and mounts precisely where the original sits. Substituting a generic switch with the wrong temperature rating can either nuisance-trip or, worse, fail to protect the system. Insist on the genuine Lennox part.