OEM Carrier Furnace Pressure Switch 1.81" WC (HK06NB123) for Model PG9MAA024040AFKA

This is the factory-specified OEM pressure switch for the Carrier PG9MAA024040AFKA gas furnace. The pressure switch is a critical safety interlock that monitors the negative pressure (draft) created by the inducer motor before allowing the ignition sequence to proceed. When it fails or becomes stuck open, the furnace control board will lock out the heating cycle — resulting in a no-heat condition, a flashing fault code, or a furnace that attempts ignition and immediately shuts down. Replacing it with the correct OEM part ensures factory-matched switching accuracy and reliable combustion safety.

• Specs: 1.81" W.C. (inches water column) setpoint | SPST (Single-Pole, Single-Throw) configuration | Standard tubing and spade terminal connections | OEM Part Number: HK06NB123
• OEM vs Generic: This OEM switch is calibrated to Carrier's exact 1.81" W.C. threshold. Aftermarket switches often carry wider pressure tolerances, which can cause nuisance lockouts or — worse — allow operation under unsafe draft conditions. OEM is always the recommended choice for pressure-critical safety components.
• Install difficulty: 2/5 — Shut off power and gas before beginning. Tools needed: flathead screwdriver, needle-nose pliers, and a short length of 5/16" rubber tubing (if replacing tubing). Photograph all hose and wire connections before removal. Snap the new switch onto the mounting bracket, reconnect the vacuum port tube and wiring terminals, then restore power and run a test cycle.
• Warranty: 1-year OEM manufacturer warranty against defects. Orders placed by 3 PM local time ship same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for Carrier model PG9MAA024040AFKA gas furnaces. Always verify the W.C. rating stamped on your existing pressure switch before ordering to confirm fitment. Our HVAC parts specialists are available to verify compatibility before you buy — just reach out before placing your order.