OEM Carrier Draft Inducer Pressure Switch 0.18" WC for Model PY4GPAA42090AA

This OEM draft pressure switch (part number HK06WC061, superseded by HK06MB061) is the factory-specified replacement for the Carrier PY4GPAA42090AA packaged heat pump/gas unit. The pressure switch proves that the draft inducer motor has established adequate negative pressure before the control board allows ignition to proceed. When this switch fails, the furnace or packaged unit will lock out before the ignition sequence begins — typically with a fault code indicating a pressure switch or inducer fault. You may also see repeated short-cycling with no heat output.

• Specs: 0.18" Water Column (W.C.) | SPST (Normally Open) | Replaces Honeywell IS20224-5236 | Factory OEM tolerance — no field calibration required
• OEM vs Generic: OEM pressure switches are calibrated to exact W.C. setpoints at the factory. Off-brand switches often carry ±0.05" W.C. tolerance variances that can cause nuisance lockouts or — worse — allow combustion with insufficient draft, creating a safety risk. Always match the W.C. rating precisely.
• Install difficulty: 2/5 — Disconnect power and gas before servicing. Tools needed: 1/4" nut driver, needle-nose pliers, and a manometer if verifying inducer performance post-install. Photograph existing tubing routing before removal. The hose barb fitting is standard 3/16" I.D. tubing.
• Warranty & Shipping: 1-year OEM factory warranty against defects. In stock — ships same business day from our warehouse.

Compatibility: Designed for the Carrier PY4GPAA42090AA packaged unit. Also crosses to Bryant and Payne models sharing the same draft inducer assembly. Note: OEM part number HK06WC061 has been superseded by HK06MB061 — both numbers are fulfilled with the current OEM production part. Verify the 0.18" W.C. rating on your existing switch or unit wiring diagram before ordering. Have questions about fitment? Our HVAC parts specialists confirm compatibility before you buy.