Lennox 36N77 Hot Surface Ignitor This genuine OEM replacement part

This genuine OEM replacement part is specifically designed for Modine PD400 and BD400 unit heaters

the R07489B003 is the current technical designation for this specific sequence relay used in Armstrong and Allied Air furnace models

Why does my 3-amp thermal breaker keep tripping

providing robust HVAC relay performance

While specifically designed for the Q624 and Q652 series

Lennox 36N77 Hot Surface Ignitor This genuine OEM replacement partThe Lennox 36N77 Hot Surface Ignitor is a critical OEM replacement part designed for high performance gas fired combustion systems. Also identified by the identical part number 36N7701, this nitride ignitor is engineered to withstand extreme thermal cycling within residential furnaces and boilers. As a direct fit HSI, it ensures precise gas ignition by delivering a robust heat source that interfaces seamlessly with the furnace's integrated control