OEM Carrier Draft Inducer Pressure Switch 0.18" WC for Model PY3GNAA24040AA

This OEM draft inducer pressure switch is the factory-specified replacement for the Carrier PY3GNAA24040AA packaged unit. The pressure switch monitors negative pressure created by the inducer motor to prove proper venting before allowing ignition to proceed. When this switch fails or sticks, the control board cannot verify safe draft conditions, resulting in a hard lockout — the furnace or packaged unit will not advance past the inducer proving stage and will not fire. Common symptoms include a system that hums briefly then shuts down, a blinking fault code indicating a pressure switch error, or a unit that runs the inducer indefinitely without ever attempting ignition.

• Specs: 0.18" Water Column (W.C.) setpoint | SPST normally open | Replaces OEM part HK06WC061 (superseded by HK06MB061) | Also replaces Honeywell IS20224-5236
• OEM vs Generic: OEM pressure switches are calibrated to the exact W.C. rating specified by Carrier engineering. Off-spec aftermarket switches can trip too early or too late, causing nuisance lockouts or — worse — allowing combustion under unsafe draft conditions.
• Install difficulty: 2/5 — Power down the unit and confirm inducer has stopped before servicing. Tools needed: 1/4" nut driver, flathead screwdriver, manometer (recommended for post-install verification). Photograph hose routing before disconnecting the pressure tube.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse.

Compatibility: Engineered for Carrier model PY3GNAA24040AA packaged units. This part supersedes HK06WC061 — if your unit's data plate or wiring diagram lists HK06WC061, this listing is the correct current OEM replacement. Verify the 0.18" W.C. rating on your existing switch before ordering. Need fitment confirmation? Our HVAC parts specialists verify compatibility before you buy — reach out before placing your order.