{"product_id":"carrier-py4gnab30040na-pressure-switch-h43sg3","title":"OEM Carrier Draft Pressure Switch 0.18\" WC for PY4GNAB30040NA","description":"\u003ch1\u003eOEM Carrier Draft Inducer Pressure Switch 0.18\" WC for Model PY4GNAB30040NA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement draft pressure proving switch for the \u003cstrong\u003eCarrier PY4GNAB30040NA\u003c\/strong\u003e packaged unit. The pressure switch monitors negative pressure created by the inducer motor to verify safe venting conditions before allowing the ignition sequence to proceed. When this switch fails or sticks open, the control board cannot confirm that the flue is drafting correctly — resulting in a \u003cstrong\u003eno-heat lockout condition\u003c\/strong\u003e that typically occurs before any ignition attempt. A failed pressure switch is one of the most common causes of furnace lockout fault codes.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 0.18\" Water Column (WC) set point | SPST (Single Pole, Single Throw) | Draft inducer proving type | Compatible with 24V control circuits | Cross-references Honeywell IS20224-5236 and 1938D2\/B\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM switches are calibrated to exact factory WC tolerances. Off-spec aftermarket switches can trip too early or too late, causing nuisance lockouts or — more dangerously — allowing ignition under unsafe venting conditions. Always match the WC rating precisely.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Power down and lockout the unit before servicing. Tools needed: 1\/4\" nut driver, flat-head screwdriver, and a multimeter to confirm switch continuity. Note the hose port orientation before removing the old switch. Replacement typically takes under 20 minutes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty \u0026amp; Shipping:\u003c\/strong\u003e 1-year OEM manufacturer warranty. In-stock orders ship same business day from our warehouse. Note: OEM part number HK06WC061 is superseded — this listing ships the current authorized replacement, HK06MB061, which is a direct, drop-in substitution.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Verified fit for Carrier model \u003cstrong\u003ePY4GNAB30040NA\u003c\/strong\u003e packaged unit. This switch also fits select Bryant and Payne models sharing the same inducer assembly. Always confirm the 0.18\" WC rating on your unit's wiring diagram or existing switch label before ordering. Our team is available to verify fitment — contact us before you order if you have any questions.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640325099891,"sku":"CARRIE-PY4GNAB30040NA-PRESSURE_SWITCH-HK06WC061","price":50.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640325132659,"sku":"CARRIE-PY4GNAB30040NA-PRESSURE_SWITCH-HK06WC061-GEN","price":44.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-pressure-switch-HK06WC061_cb19eaf4-0304-4b91-b5ba-be394769f70b.jpg?v=1775027583","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py4gnab30040na-pressure-switch-h43sg3","provider":"National HVAC Parts","version":"1.0","type":"link"}