OEM Carrier Draft Inducer Pressure Switch 0.18" WC for Model PY4GPAA60090AA

This is the factory-specified OEM replacement pressure switch for the Carrier PY4GPAA60090AA packaged unit. The draft inducer pressure switch is a critical safety component that monitors negative pressure inside the heat exchanger flue — confirming that the inducer motor has established proper airflow before allowing the ignition sequence to proceed. When this switch fails or sticks, the control board cannot verify safe venting conditions, resulting in a no-heat lockout, a blinking fault code, or a furnace that attempts ignition but immediately shuts down. Common causes of failure include a cracked rubber hose, a plugged condensate port, a weak inducer motor, or a mechanically failed switch diaphragm.

• Specs: 0.18" WC (inches water column) setpoint | SPST (Single Pole, Single Throw) | Draft-proving / negative-pressure type | Factory-matched Honeywell switch assembly (cross-ref: IS20224-5236)
• OEM vs Generic: This OEM switch meets exact Carrier factory tolerances. Aftermarket pressure switches frequently deviate from the rated W.C. setpoint, causing nuisance lockouts or — more dangerously — allowing ignition under unsafe venting conditions. OEM is the only recommended choice for a safety-critical component.
• Install Difficulty: 2/5 — Standard hand tools required: 1/4" nut driver, flat-head screwdriver, and needle-nose pliers. Disconnect power and gas before servicing. Inspect the rubber hose connecting the switch to the inducer for cracks or blockages before installing the new switch — a faulty hose causes the same symptoms as a bad switch.
• Warranty & Shipping: Backed by a 1-year OEM manufacturer warranty. In stock and ships same business day from our warehouse when ordered by 3 PM local time.

Supersession Note: OEM part number HK06WC061 has been superseded by HK06MB061. Both part numbers are cross-referenced here — you will receive the current production replacement, which is a direct drop-in for the original. Compatible with Carrier, Bryant, and Payne platforms sharing this pressure switch specification. Verify the 0.18" WC rating on your unit's wiring diagram or data plate before ordering. Our parts specialists are available to confirm fitment — contact us before you order.