OEM Lennox Limit Switch — 28G80

The genuine OEM Lennox 28G80 limit switch is a critical safety control that monitors temperature inside compatible Lennox furnaces and heating equipment. It signals the control board to shut off the burners if the heat exchanger or plenum exceeds a safe temperature, protecting the system and your home from overheating, and it also helps coordinate blower operation during the heating cycle.

Common failure symptoms: A faulty limit switch commonly causes the furnace to short cycle, shut down on a limit fault, or fail to fire at all. You may also see the blower running continuously, inadequate heat output, or repeated safety lockouts. Because this switch protects against dangerous overheating, any erratic behavior should be addressed promptly.

Why OEM matters: The 28G80 is calibrated to a specific trip and reset temperature that matches your Lennox unit's design. Substituting a switch with the wrong temperature rating or terminal configuration can cause nuisance shutdowns or, worse, disable a vital safety function. Installing the authentic OEM Lennox part restores the exact factory protection and reliable operation your heating system depends on.