{"product_id":"carrier-fiop300c501ga-pressure-switch-jri7yl","title":"OEM Carrier High Pressure Switch HK02ZA442 for FIOP300C501GA","description":"\u003ch1\u003eOEM Carrier High Pressure Switch HK02ZA442 for Model FIOP300C501GA\u003c\/h1\u003e\u003cp\u003eThis is the OEM factory-specified high pressure switch (part number \u003cstrong\u003eHK02ZA442\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier FIOP300C501GA\u003c\/strong\u003e unit. The pressure switch is a critical safety component that monitors the inducer motor's ability to create proper draft before allowing the ignition sequence to proceed. When the switch detects insufficient negative pressure — due to a blocked flue, failed inducer motor, cracked hose, or a faulty switch itself — it interrupts the ignition sequence and puts the system into lockout. Common symptoms of a failed pressure switch include the furnace or air handler refusing to advance past the inducer stage, repeated fault codes related to pressure or draft proving, and a system that attempts ignition but immediately locks out.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e High pressure switch | OEM part number HK02ZA442 | Factory-calibrated W.C. (water column) rating | Direct plug-in wiring harness connector for tool-free electrical connection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM switch is factory-calibrated to the exact water column rating required by the \u003cstrong\u003eFIOP300C501GA\u003c\/strong\u003e. Aftermarket pressure switches often carry wider tolerances that can cause nuisance lockouts or — more dangerously — fail to trip when a true venting problem exists.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Shut off power and gas before beginning. Tools needed: flathead screwdriver, needle-nose pliers, and a digital manometer (recommended to verify W.C. after install). Photograph all hose and wiring connections before removal. Swap hoses one at a time to avoid mis-routing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In stock and ships same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed specifically for the Carrier \u003cstrong\u003eFIOP300C501GA\u003c\/strong\u003e. Always cross-reference the W.C. rating stamped on your existing switch with the HK02ZA442 spec sheet to confirm fitment on variant configurations. Our HVAC parts specialists are available to verify compatibility before you order — reach out before placing your order if you have any questions. \u003cstrong\u003eOrder today and receive same-day shipping on all in-stock parts.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909503275379,"sku":"CARRIE-FIOP300C501GA-PRESSURE_SWITCH-HK02ZA442","price":27.0,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909503308147,"sku":"CARRIE-FIOP300C501GA-PRESSURE_SWITCH-HK02ZA442-GEN","price":19.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-draft-inducer-HK02ZA442_07190c14-4c06-4a49-a798-9d44a89136b5.jpg?v=1782924890","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fiop300c501ga-pressure-switch-jri7yl","provider":"National HVAC Parts","version":"1.0","type":"link"}