OEM Carrier Pressure Switch HK02ZB044 — 7# Open / 22# Close for Model PH1REA048000AAWA

This OEM pressure switch (part number HK02ZB044) is the factory-specified replacement for the Carrier PH1REA048000AAWA packaged unit. The pressure switch monitors the negative pressure (draft) produced by the inducer motor to confirm proper venting before allowing ignition to proceed. When the switch fails or becomes stuck open, the control board cannot verify a safe venting condition — resulting in a no-heat lockout, a blinking fault code, or a system that cycles the inducer repeatedly without ever reaching ignition. If your unit is stuck at the beginning of the heating sequence and no igniter glow is observed, a failed pressure switch is one of the most common culprits.

• Specs: Opens at 7" W.C. | Closes at 22" W.C. | 50" lead wires | 24V control circuit | Manufactured in Mexico to OEM factory standards
• OEM vs Generic: This is the genuine Carrier OEM part. Generic pressure switches often carry wider pressure tolerances that can cause nuisance lockouts or, worse, fail to detect a true venting problem — a potential safety risk on any gas-fired appliance.
• Install difficulty: 2/5 — Shut off gas and power before servicing. Tools needed: 1/4" nut driver, needle-nose pliers, a manometer (recommended to verify inducer draft). Photograph all hose and wire connections before removal. The switch snaps in and leads connect to spade terminals.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before 3 PM local time.

Compatibility: Designed as a factory replacement for the Carrier PH1REA048000AAWA packaged unit. Verify your existing switch's W.C. rating and lead length against your unit's data plate before ordering. Our HVAC parts specialists are available to confirm fitment — contact us before you order if you have any questions.