Lennox 52M73 Rollout Switch Overview
The Lennox 52M73 is a manual reset rollout switch engineered to protect furnaces and heating systems from the hazards of burner flame rollout. When abnormal combustion causes flames to extend beyond the burner compartment, this switch detects the elevated temperature and immediately interrupts the circuit, shutting down the burner to prevent heat exchanger damage, equipment failure, or potential fire hazard.
Key Features
- Trip temperature: 350°F — triggers protective shutdown at dangerous flame rollout temperatures
- Manual reset design — requires intentional technician reset after a trip event, ensuring the root cause is identified and corrected before resuming operation
- SPST (Single Pole, Single Throw) switching configuration for straightforward circuit interruption
- Direct OEM replacement for compatible Lennox furnace models
- Durable construction designed to withstand the high-heat environment of the burner compartment
Why Manual Reset Matters
Unlike automatic-reset switches, a manual reset rollout switch will not allow the system to restart on its own after a fault. This is a critical safety feature — if flame rollout has occurred, a qualified HVAC technician must inspect the system, diagnose the underlying cause (such as a cracked heat exchanger, blocked flue, or restricted airflow), and manually reset the switch before the furnace can operate again. This prevents repeated unsafe cycling and protects both equipment and occupants.
Application
- Replacement rollout switch for select Lennox gas furnaces
- Installs in the burner compartment near the burner assembly
- Compatible with systems requiring a 350°F trip-point, manual reset, SPST rollout switch
Specifications
- Brand: Lennox
- Part Number / SKU: 52M73
- Trip Temperature: 350°F
- Reset Type: Manual Reset
- Switch Configuration: SPST (Single Pole, Single Throw)
- Switch Type: Rollout Switch
