{"product_id":"carrier-c4850c50ay03561-transformer-h302a1","title":"OEM Carrier Transformer 40VA 120V to 24V for C4850C50AY03561 — Ships Today","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C50AY03561\u003c\/h1\u003e\u003cp\u003eThis OEM step-down transformer (part number \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier C4850C50AY03561\u003c\/strong\u003e packaged unit. The transformer steps down 120V line voltage to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When this part fails, the system goes completely silent: the thermostat display may go blank, the contactor won't energize, and no heating or cooling operation is possible. If you've confirmed 120V supply at the unit but zero 24V output at the secondary terminals, this transformer is the likely culprit.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01BD236 | Factory-matched output tolerance for stable control voltage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and insulated to exact factory specifications, ensuring consistent 24V output under load. Generic alternatives can sag under full control-circuit load, causing intermittent lockouts, nuisance trips, or premature control board failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Label or photograph all low-voltage wiring before disconnecting. Verify 24V output at secondary after installation before restoring full power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects. In stock and ships 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\u003eC4850C50AY03561\u003c\/strong\u003e packaged unit. Always verify your existing transformer's VA rating, primary voltage, and secondary voltage on the unit's data plate or wiring diagram before ordering. Need fitment confirmation? Our HVAC parts specialists are available to verify compatibility before you buy — order with confidence and get back up and running today.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909811360115,"sku":"CARRIE-C4850C50AY03561-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909811392883,"sku":"CARRIE-C4850C50AY03561-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_08efe994-687a-4bcc-908c-169a0922220e.jpg?v=1782938958","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c50ay03561-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}