Lennox 45K27 Flue Gasket 320720-756 always cross-reference the Aaon replacement

always cross-reference the Aaon replacement parts manual to confirm compatibility with your specific heat exchanger configuration and burner assembly

these part numbers are technical equivalents and represent the same physical component

turn the adjustment screw counter-clockwise until it stops

this specific model is engineered with a 1/2 inch bore

which is essential for multi-stage heating and cooling performance

Lennox 45K27 Flue Gasket 320720-756 always cross-reference the Aaon replacementThe Lennox 45K27 Flue Gasket (also identified by part number LB 66251) is an essential OEM component for maintaining the structural integrity of the exhaust system in high efficiency gas furnaces and commercial rooftop units. Designed to withstand the thermal stress of combustion cycles, this high temperature flue gasket creates a critical airtight seal between the flue pipe and the furnace transition. By preventing the leakage of combustion by