OEM Carrier Dual Pressure Switch Assembly 0.80"/1.70" W.C. for Model PG9YAB048080AAAA

This OEM dual pressure switch assembly is the factory-specified replacement for the Carrier PG9YAB048080AAAA 2-stage gas furnace. Mounted on a Honeywell 27555BM-01 bracket, it contains two individual pressure switches that monitor inducer motor vacuum at 0.80" and 1.70" W.C. respectively — one for each stage of heat. The control board will not allow ignition until both switches confirm that the draft inducer is producing sufficient negative pressure to safely vent combustion gases. When this assembly fails, the inducer motor runs normally but the furnace locks out before the burners ever fire — a classic pressure switch failure symptom.

• Specs: Dual switch assembly | Stage 1: -0.80" W.C. | Stage 2: -1.70" W.C. | Mounted on Honeywell 27555BM-01 bracket | OEM Part # HK06NA016 (superseded by HK06MB025) | Honeywell cross-reference: BA20238
• OEM vs Generic: OEM switches are factory-calibrated to exact W.C. set points. Off-spec generic switches can allow unsafe flue conditions or cause chronic nuisance lockouts — always use OEM on pressure-proving safety components.
• Install difficulty: 3/5 — Turn off power and gas before starting. Tools needed: flat-head screwdriver, needle-nose pliers, phone or camera (photograph hose and wiring routing before disassembly). Remove both access panels, disconnect two pressure hoses and wiring terminals, unbolt the bracket, and reverse to install. Reconnect hoses to their matching ports — mixing them causes immediate lockout.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered for the Carrier PG9YAB048080AAAA 2-stage 80,000 BTU gas furnace. Also fits related Carrier, Bryant, and Payne models using the HK06NA016 / HK06MB025 specification. Always verify the W.C. rating on your existing switch label before ordering. Our fitment team is available to confirm compatibility before you buy.