OEM Carrier Draft Pressure Switch 0.18" WC for Model PY3GNAA48115AA

This OEM draft pressure proving switch is the factory-specified replacement for the Carrier PY3GNAA48115AA packaged unit. Rated at 0.18" water column (WC), this SPST switch monitors negative pressure created by the inducer blower to confirm safe venting conditions before allowing ignition to proceed. When it fails — or when the tubing cracks, the inducer wheel is dirty, or the port is blocked — the control board never receives the "safe to ignite" signal, resulting in a no-heat lockout. Technicians will typically find a pressure switch fault code on the board.

• Specs: 0.18" WC set point | SPST (Single-Pole, Single-Throw) | Normally open | OEM Part# HK06WC061 (superseded by HK06MB061) | Honeywell cross-reference: IS20224-5236
• OEM vs Generic: This is a genuine Carrier OEM switch manufactured to exact factory tolerances. Generic aftermarket switches frequently exhibit set-point drift, incorrect port sizing, or premature diaphragm failure — all of which cause nuisance lockouts or unsafe operation.
• Install difficulty: 2/5 — Turn off power and gas before beginning. Tools needed: 1/4" nut driver, needle-nose pliers, and a manometer to verify inducer static pressure post-install. Always inspect the rubber hose barb for cracks and replace tubing if brittle or collapsed.
• Warranty: 1-year OEM factory warranty. In-stock and ships same business day from our warehouse.

Compatibility: Engineered for Carrier model PY3GNAA48115AA packaged gas/electric units. Also fits select Bryant and Payne models sharing this pressure rating — verify your unit's data plate and existing switch WC rating before ordering. Note: HK06WC061 was officially discontinued in December 2024 and fulfilled by superseding OEM part HK06MB061 — a direct, drop-in replacement. Questions about fitment? Our HVAC parts specialists verify compatibility before you order.