OEM Lennox Armstrong Ducane Furnace Pressure Switch Fits MPL 9371VO-HS-0143 0.68
OEM MPL Lennox Armstrong Furnace Air Pressure Switch 9371VO-HS-0143 -0.68″. An air switch is safety designed to ensure that your inducer motor is running at the proper RPM, and creating the proper vacuum for your furnace to flue safely.