OEM Payne High & Low Pressure Switch for Model PA13NR024000AAAA

These OEM pressure switches — HK02ZA395 (High Pressure Switch) and HK02ZB028 (Low Pressure Switch) — are the factory-specified replacements for the Payne PA13NR024000AAAA split-system heat pump. Pressure switches monitor refrigerant pressures on both the high and low sides of the refrigerant circuit, protecting the compressor from operating outside safe pressure ranges. When either switch fails or trips, the system will lock out before completing a heating or cooling cycle — often with a fault code indicating a pressure fault or open safety circuit.

• Specs: HK02ZA395 — High-Side Pressure Switch | HK02ZB028 — Low-Side Pressure Switch | Factory-calibrated set points | 24V control circuit compatible | Spade terminal connections
• OEM vs Generic: OEM pressure switches are calibrated to exact factory cut-in and cut-out pressures for the PA13NR024000AAAA refrigerant circuit. Aftermarket switches frequently ship with looser tolerances, risking nuisance trips or, worse, failing to protect the compressor under genuine fault conditions.
• Install difficulty: 3/5 — Refrigerant circuit work requires EPA 608 certification. Control-side wiring replacement is straightforward: photograph existing wiring, disconnect spade terminals, swap switch, restore wiring. Tools needed: flathead screwdriver, needle-nose pliers, multimeter for continuity verification. Always de-energize the unit at the disconnect before servicing.
• Warranty: 1-year OEM factory warranty on both switches. Orders placed before cutoff ship same business day from our warehouse.

Compatibility: Both switches are engineered specifically for the Payne PA13NR024000AAAA 2-ton single-stage split-system heat pump. Confirm your existing switch part numbers (HK02ZA395 or HK02ZB028) against your unit's wiring diagram or service label before ordering. Need help confirming fitment? Our HVAC parts specialists verify compatibility before you buy.