OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
The genuine OEM Lennox 83L83 limit switch is a temperature-sensing safety control for your Lennox gas furnace. It watches the heat exchanger area and opens the burner circuit if temperatures climb beyond the safe threshold, preventing overheating damage and shutting the system down before a hazard develops.
Common failure symptoms: A worn or failed 83L83 commonly causes short cycling, furnace lockouts, blower operation without heat, or intermittent no-heat complaints. Over time the switch's trip point can drift, leading to nuisance shutdowns even when the furnace is otherwise healthy.
Why OEM matters: Lennox calibrates the 83L83 to an exact setpoint and terminal layout specific to your equipment. The genuine OEM part restores the correct safety response and provides a true drop-in fit — avoiding the calibration errors and fitment issues that plague universal aftermarket switches, and helping maintain your Lennox warranty.