verifying the part number cross-reference between the N800-9423 and the 21-841 is the first step in resolving air leaks or erratic actuator response

though we recommend verifying the proportional control signal settings via the internal DIP switches during commissioning

This fan blade is designed for clockwise (CW) rotation when viewing the hub from the intake side

one-handed installation or removal without the need for manual linkages or complex calibration

York S1-7990-6501 Booster Assembly 30067439-890 verifying the part number cross-referenceThe York S1 7990 6501 Booster Assembly is a critical OEM replacement part designed for high efficiency gas furnaces within the York, Coleman, and Luxaire families. This BDF Vent Booster Assembly is engineered to facilitate proper flue gas evacuation, ensuring the pressure switch closes to allow the ignition sequence to proceed. As a centrifugal blower, it manages the venting of combustion byproducts safely out of the heat exchanger. When diagnosing a