OEM Carrier Pressure Switch with Bracket for Model PG8UAA042091ABJA — HK06WC090

This OEM pressure switch with bracket (part number HK06WC090) is the factory-specified replacement for the Carrier PG8UAA042091ABJA gas furnace. The pressure switch is a critical safety device that monitors the negative pressure (inches water column) generated by the inducer draft motor during each heating cycle. Once the inducer reaches the correct speed and negative pressure, the switch closes, signaling the control board that it is safe to proceed with ignition. When this switch fails — or its hose, port, or diaphragm degrades — the furnace will lock out before ignition, leaving you with no heat. Common symptoms include the inducer running continuously with no ignition, a flashing fault code indicating an open pressure switch, or a furnace that short-cycles immediately after startup.

• Specs: Factory-rated W.C. (inches water column) setpoint matched to the PG8UAA042091ABJA inducer assembly | Includes OEM mounting bracket for direct drop-in installation | SPST normally-open contact configuration | 1/4" barbed inlet port
• OEM vs Generic: This is a genuine OEM Carrier part, manufactured to the exact W.C. setpoint and diaphragm specification for your unit. Aftermarket pressure switches may carry incorrect trip points, causing nuisance lockouts or — more dangerously — failing to detect true inducer faults.
• Install difficulty: 2/5 — Shut off gas and power before servicing. Tools needed: 1/4" nut driver, flat-head screwdriver, manometer (recommended to verify W.C. after install). Photograph hose routing and wiring terminals before disconnecting. Inspect the rubber hose for cracks or blockages before condemning the switch.
• Warranty: 1-year OEM factory warranty against defects. In-stock and ships same business day from our warehouse.

Compatibility: Designed as a direct OEM replacement for the Carrier PG8UAA042091ABJA packaged gas furnace. Verify your existing switch's W.C. rating and port count on the unit's data plate or wiring diagram before ordering. Not sure if this fits? Our HVAC parts specialists confirm fitment before you buy — contact us before placing your order.