OEM Payne High & Low Pressure Switch for Model PA12NA03600GAAAA

These OEM pressure switches — HK02ZA395 (High Pressure Switch) and HK02ZB028 (Low Pressure Switch) — are the factory-specified replacements for the Payne PA12NA03600GAAAA heat pump system. Pressure switches monitor refrigerant-side pressures to protect the compressor and refrigerant circuit from operating outside safe limits. When either switch fails or trips, the system will lock out, refuse to start, or cycle off unexpectedly — often displaying a fault code related to high- or low-pressure protection.

• Specs: HK02ZA395 — High Pressure Switch, factory-calibrated cutout set point | HK02ZB028 — Low Pressure Switch, factory-calibrated cutout set point | Both designed for R-410A refrigerant systems | OEM-matched electrical connectors for direct plug-in replacement
• OEM vs Generic: OEM pressure switches are factory-calibrated to exact trip and reset pressures for the PA12NA03600GAAAA. Generic substitutes frequently use off-spec set points that can allow compressor damage or cause nuisance lockouts, shortening system life.
• Install difficulty: 3/5 — Refrigerant-side work should only be performed by an EPA 608-certified technician. Tools needed: manifold gauge set, multimeter, flathead and Phillips screwdrivers, adjustable wrench. Always recover refrigerant per EPA regulations before replacing pressure switches in the refrigerant circuit.
• Warranty: 1-year OEM factory warranty on both switches. Orders ship same business day from our warehouse when placed before 3 PM local time.

Compatibility: Designed specifically for the Payne PA12NA03600GAAAA heat pump condenser. Confirm OEM part numbers HK02ZA395 and HK02ZB028 against your unit's wiring diagram or data plate before ordering. Our fitment specialists are available to verify compatibility — contact us before you order if you have any questions.