OEM Payne High & Low Pressure Switch for Model PA11JA024000AAAA

These OEM pressure switches — HK02ZA395 (High Pressure Switch) and HK02ZB028 (Low Pressure Switch) — are the factory-specified replacements for the Payne PA11JA024000AAAA system. Pressure switches monitor the inducer motor's draft pressure to confirm safe venting conditions before allowing the ignition sequence to proceed. When either switch fails, the control board cannot verify proper airflow, causing the system to lock out before ignition — leaving you with no heat and a blinking fault code.

• Specs: HK02ZA395 — High Pressure Switch | HK02ZB028 — Low Pressure Switch | Factory-calibrated W.C. (water column) rating | SPST normally-open contacts | OEM-matched connector and port diameter for direct drop-in fitment
• OEM vs Generic: OEM pressure switches are precision-calibrated to the exact water column rating required by your Payne system. Off-brand substitutes often ship with loose tolerances, causing nuisance lockouts or — worse — failing to trip under genuinely unsafe draft conditions.
• Install difficulty: 3/5 — Shut off power and gas before beginning. Tools needed: 1/4" nut driver, flathead screwdriver, manometer (recommended to verify W.C. rating after install), and a multimeter to confirm switch continuity. Photograph all tubing and wiring connections before disconnecting. Clear any condensate from the pressure port tubing before installing the new switch.
• Warranty: 1-year OEM factory warranty. Orders received by 3 PM local time ship same business day from our climate-controlled warehouse.

Compatibility: Engineered specifically for the Payne PA11JA024000AAAA. Both the high-pressure switch (HK02ZA395) and low-pressure switch (HK02ZB028) are listed together — confirm your fault code or failed switch with a multimeter before ordering the correct switch for your repair. If you are unsure which switch has failed, our HVAC parts specialists can help verify fitment before you buy. Order today and get back to heat fast.