OEM Carrier Draft Inducer Pressure Switch 0.18" WC for Model PY4GPAB48090AA

This OEM draft pressure switch (part number HK06WC061, now superseded by HK06MB061) is the factory-specified replacement for the Carrier PY4GPAB48090AA packaged unit. The pressure switch monitors the negative pressure created by the draft inducer blower to confirm proper venting before allowing the ignition sequence to proceed. When it fails or sticks open, the control board cannot verify safe venting conditions and will lock out the system entirely — leaving you with no heat and often a fault code pointing to inducer or pressure switch failure.

• Specs: 0.18" W.C. (water column) setpoint | SPST (Single-Pole, Single-Throw) | Normally open | Compatible with Carrier, Bryant, and Payne packaged units and furnaces | Supersedes OEM part HK06WC061 → current part HK06MB061
• OEM vs Generic: OEM pressure switches are factory-calibrated to exact W.C. setpoints. Generic alternatives often drift ±0.05" WC or more, causing nuisance lockouts or — more dangerously — allowing ignition under marginal venting conditions. Always match the rated W.C. exactly.
• Install Difficulty: 2/5 — Straightforward single-screw mount and hose barb connection. Tools needed: 1/4" nut driver, flathead screwdriver, and a multimeter to confirm continuity before and after replacement. Always disconnect power at the breaker before beginning work. Inspect the rubber hose and hose barb for cracks while the unit is open.
• Warranty: 1-year OEM manufacturer warranty. In-stock units ship same business day when ordered by 3 PM local time.

Compatibility: Verified fit for Carrier model PY4GPAB48090AA packaged unit. This switch also fits a broad range of Carrier, Bryant, and Payne furnaces and packaged units sharing the 0.18" WC specification — confirm your unit's existing switch W.C. rating from the data plate or wiring diagram before ordering. Have questions about fitment? Our HVAC parts specialists verify compatibility before you order — reach out before you buy.