Lennox 45K27 Flue Gasket 319847-401 this is a combined regulator

this is a combined regulator and modulating valve

You must never install a relief valve with a pressure rating lower than the system's maximum allowable working pressure (MAWP)

it features heavy-duty construction to withstand high-temperature environments without premature thermal degradation

Installation Efficiency: The Type D plug-in design with spade and pin terminals streamlines the replacement process for service technicians

and motor circuits

Lennox 45K27 Flue Gasket 319847-401 this is a combined regulatorThe 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