OEM Carrier LP Gas Pressure Switch — HK02LB008 / HK06WC091 / HK06WC100 for Model PG8MAA048070AGJA

This is the factory OEM gas pressure switch assembly for the Carrier PG8MAA048070AGJA packaged gas/electric unit. The pressure switch monitors the negative pressure (draft) produced by the inducer motor and proves that the heat exchanger is safely venting combustion gases before allowing the gas valve to open. A failed pressure switch is one of the most common causes of a no-heat lockout — the inducer will run, but the furnace will fault out before ever reaching ignition because the board never receives the pressure-proven signal.

• Specs: LP (propane) gas pressure switch | Cut-out set point: 6.5" W.C. | SPST normally-open | Cross-references OEM part numbers HK02LB008, HK06WC091, and HK06WC100 (bracket-mount variant) | Factory-authorized replacement (GFS3451-4036)
• OEM vs Generic: OEM pressure switches are factory-calibrated to exact W.C. tolerances for the PG8MAA048070AGJA heat exchanger. Generic switches can drift ±10–15% from rated cut-out pressure, causing nuisance lockouts or — more dangerously — allowing operation with a compromised draft. Always use OEM on gas-fired equipment.
• Install Difficulty: 2/5 — Disconnect power and gas before beginning. Tools needed: 1/4" nut driver, flat-head screwdriver, needle-nose pliers, and a digital manometer to verify draft pressure post-install. The HK06WC100 variant includes a factory bracket; confirm your existing mounting style before ordering. Photograph all wiring and hose connections before removal.
• Warranty & Shipping: 1-year OEM manufacturer warranty against defects. In stock — ships same business day from our warehouse. Tracked freight included.

Compatibility & Cross-Reference: Fits Carrier PG8MAA048070AGJA packaged gas/electric units. This listing covers all three OEM part numbers: HK02LB008 (gas pressure switch), HK06WC091 (pressure switch), and HK06WC100 (pressure switch with bracket). Also fits select Bryant and Payne models with the same LP pressure specification — verify the 6.5" W.C. cut-out rating on your unit's data plate before ordering. Questions about fitment? Our HVAC parts specialists confirm compatibility before you buy.