{"product_id":"carrier-c4850c50aj05161-transformer-h302a1","title":"OEM Carrier 40VA 120V to 24V Control Transformer for C4850C50AJ05161 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C50AJ05161\u003c\/h1\u003e\u003cp\u003eThis OEM replacement transformer (part number \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified step-down transformer for the \u003cstrong\u003eCarrier C4850C50AJ05161\u003c\/strong\u003e packaged unit. The transformer converts 120V line voltage to the 24V AC signal that powers the entire control circuit — including the thermostat, contactor coil, gas valve, and control board. When it fails, nothing in the system responds: the thermostat goes blank, the unit refuses all commands, and you may measure zero voltage on the secondary (24V) side. A failed transformer is often caused by a shorted control wire or a failed component drawing excess current, so always inspect the control circuit before replacing.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e Primary voltage: 120V AC | Secondary voltage: 24V AC | VA rating: 40VA | OEM part number: HT01BD236 | Factory-matched output tolerances\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and potted to Carrier's exact specifications, ensuring stable 24V output under full load. Generic units often under-deliver under peak demand, causing nuisance lockouts, erratic thermostat behavior, and premature contactor wear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire stripper. Verify 0V on primary terminals before touching wiring. Photograph all connections before disconnecting. Test secondary output (should read 24–28V AC) after installation before closing panels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In-stock units ship same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered specifically for the Carrier \u003cstrong\u003eC4850C50AJ05161\u003c\/strong\u003e packaged unit. Confirm your unit's control circuit voltage (120V primary \/ 24V secondary) and VA rating on the unit data plate before ordering. Our fitment team is available to verify compatibility before you buy — same-day shipping on all in-stock OEM parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909835149683,"sku":"CARRIE-C4850C50AJ05161-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909835182451,"sku":"CARRIE-C4850C50AJ05161-TRANSFORMER-HT01BD236-GEN","price":18.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-HT01BD236_a2744f05-e801-49e2-9b83-92500587f7de.jpg?v=1782899112","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c50aj05161-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}