{"product_id":"payne-pa12na048000adaa-pressure-switch-jria74","title":"OEM Payne Pressure Switch Set for PA12NA048000ADAA (HK02ZA395 \/ HK02ZB","description":"\u003ch1\u003eOEM Payne High \u0026amp; Low Pressure Switch Set for Model PA12NA048000ADAA\u003c\/h1\u003e\u003cp\u003eThese OEM pressure switches are the factory-specified replacements for the \u003cstrong\u003ePayne PA12NA048000ADAA\u003c\/strong\u003e packaged air conditioning unit. Pressure switches prove that the system's refrigerant pressures are within safe operating limits before allowing the control board to proceed through the start sequence. When either the high-pressure switch (\u003cstrong\u003eHK02ZA395\u003c\/strong\u003e) or low-pressure switch (\u003cstrong\u003eHK02ZB028\u003c\/strong\u003e) fails, the unit will typically lock out before or during the cooling cycle, display a fault code, or short-cycle repeatedly without delivering conditioned air. A failed pressure switch is one of the most common causes of a no-cooling complaint on packaged units.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e Includes HK02ZA395 (High Pressure Switch) and HK02ZB028 (Low Pressure Switch) | Factory-calibrated trip points | Normally-open\/normally-closed contacts per OEM specification | Designed for R-410A refrigerant systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM pressure switches are calibrated to exact factory trip-point tolerances, ensuring the system locks out at the correct pressure threshold. Generic alternatives can drift out of spec, causing nuisance lockouts or — more dangerously — failing to protect the compressor from true over- or under-pressure conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 3\/5\u003c\/strong\u003e — Refrigerant-side pressure switches require recovery of refrigerant before replacement on the high-side or low-side ports. Tools needed: manifold gauge set, refrigerant recovery equipment, adjustable wrench, and a multimeter to confirm continuity. Always follow EPA Section 608 regulations when working with refrigerants. Recommended for licensed HVAC technicians.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty on both switches. Orders ship same business day from our warehouse when placed before 3 PM local time.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e This listing covers both the high-pressure switch (HK02ZA395) and low-pressure switch (HK02ZB028) for the \u003cstrong\u003ePayne PA12NA048000ADAA\u003c\/strong\u003e 4-ton packaged air conditioning unit. Always verify your existing switch part numbers against the unit's data plate and wiring diagram before ordering. Our fitment team is available to confirm compatibility before you buy — contact us anytime.\u003c\/p\u003e","brand":"Payne","offers":[{"title":"OEM","offer_id":62909181133171,"sku":"PAYNE-PA12NA048000ADAA-PRESSURE_SWITCH-HK02ZA395","price":43.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909181165939,"sku":"PAYNE-PA12NA048000ADAA-PRESSURE_SWITCH-HK02ZA395-GEN","price":38.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-pressure-switch-HK02ZA395_33f5720e-44de-4e9b-91ed-ac0de10ed50a.jpg?v=1780718637","url":"https:\/\/nationalhvacparts.com\/products\/payne-pa12na048000adaa-pressure-switch-jria74","provider":"National HVAC Parts","version":"1.0","type":"link"}