OEM Payne High & Low Pressure Switch for Model PA10JA018000ACAA

These OEM pressure switches — HK02ZA395 (High Pressure Switch) and HK02ZB028 (Low Pressure Switch) — are the factory-specified replacements for the Payne PA10JA018000ACAA packaged air conditioning unit. Pressure switches prove that the refrigerant circuit is operating within safe high- and low-side pressure limits before allowing the system to proceed through its cooling cycle. When either switch fails or sticks open, the control board receives no confirmation signal and locks the unit out — resulting in a no-cool condition, repeated fault codes, or a system that trips immediately after startup.

• Specs: High-side switch OEM part HK02ZA395 | Low-side switch OEM part HK02ZB028 | Factory-calibrated W.C. setpoints matched to PA10JA018000ACAA refrigerant circuit | Spade terminal connectors | OEM-matched pressure thresholds for R-410A operation
• OEM vs Generic: OEM pressure switches are calibrated to exact factory open/close pressure setpoints. Generic alternatives frequently carry wider tolerances that can allow unsafe operating pressures to go undetected, risking compressor damage or nuisance lockouts.
• Install Difficulty: 3/5 — Refrigerant circuit work requires an EPA 608 certified technician. Tools needed: manifold gauge set, flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Always recover refrigerant per EPA regulations before accessing the refrigerant circuit. Photograph all wiring before disconnecting.
• Warranty: 1-year OEM factory warranty on both HK02ZA395 and HK02ZB028. In-stock units ship same business day from our warehouse.

Compatibility: Engineered specifically for the Payne PA10JA018000ACAA packaged air conditioning unit. Verify your existing switch part numbers against HK02ZA395 and HK02ZB028 on your unit's data plate or wiring diagram before ordering. Our fitment specialists are available to confirm compatibility prior to purchase — order with confidence and get your system back online fast.