OEM Carrier Low Pressure Switch HK02ZB044 — 7 PSI Open / 22 PSI Close for Model PH1RPA090000AAWB

This is the genuine OEM Carrier low pressure switch (part #HK02ZB044) factory-specified for the Carrier PH1RPA090000AAWB packaged heat pump unit. The pressure switch is a critical safety and proving device in the refrigerant circuit: it monitors system pressure and interrupts operation if pressure falls outside the designed range. When this switch fails or sticks open, the unit will typically enter a lockout condition, refuse to stage into heating or cooling, or short-cycle immediately after startup — symptoms that are often misdiagnosed as a refrigerant or control board issue.

• Specs: Opens at 7 PSI | Closes at 22 PSI | 50" wire leads | 24V control circuit | Manufactured in Mexico to OEM design tolerances
• OEM vs Generic: This is a genuine Carrier OEM part. OEM pressure switches are calibrated to exact cut-in/cut-out setpoints. Aftermarket alternatives often carry wider tolerances that can cause nuisance trips, erratic system behavior, or premature failure — particularly in variable-load packaged units like the PH1RPA090000AAWB.
• Install difficulty: 2/5 — Shut off all power to the unit at the disconnect before beginning. Tools needed: 1/4" nut driver or 5/16" wrench, needle-nose pliers, and a multimeter for continuity verification. Photograph or label existing wire positions before disconnecting. The 50" leads provide ample routing flexibility. No soldering required.
• Warranty: 1-year OEM factory warranty. In-stock units ship same business day from our warehouse when ordered before cutoff.

Compatibility: Designed as a direct OEM replacement for the Carrier PH1RPA090000AAWB packaged heat pump. Verify your unit's data plate and existing switch setpoints (7# open / 22# close) before ordering to ensure correct fitment. Our HVAC parts specialists are available to confirm compatibility before you buy — no guesswork, no return hassle. Order today and get it shipped fast.