Lennox 77M09 Box 321894-708 or up to 50% ethylene

or up to 50% ethylene glycol

Always verify the temperature stamping on your existing switch to ensure a 115/85 match

Efficiency: Captures large airborne particles like dust

Designed for reliability in high-cycle environments

Lennox 77M09 Box 321894-708 or up to 50% ethyleneThe Lennox 77M09 Burner Box Side is a vital structural and functional component engineered for high efficiency gas furnace maintenance. As a critical part of the combustion housing assembly, this side panel provides the necessary containment for the burner sparks and flames, ensuring that thermal energy is channeled directly into the heat exchanger. For contractors performing a Lennox HVAC repair, the 77M09 serves as more than just a metal plate; it