{"product_id":"carrier-c48a502551-transformer-h302a1","title":"OEM Carrier Transformer 40VA 120V\/24V for C48A502551","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA for Model C48A502551\u003c\/h1\u003e\u003cp\u003eThis is the factory-specified OEM replacement transformer (part number \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier C48A502551\u003c\/strong\u003e packaged unit. The control transformer steps down 120V line voltage to the 24V signal that powers your thermostat, contactor coil, and control board. When it fails, the entire control circuit goes dead — the thermostat shows no response, the system won't call for cooling or heating, and nothing happens when you adjust the setpoint. It's one of the first components to check when a system appears completely unresponsive despite having line voltage.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Direct OEM replacement | Part number HT01BD236 | Factory-matched output voltage for reliable control circuit operation\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM transformer is wound to Carrier's exact VA and voltage specifications. Generic transformers with undersized VA ratings can overheat under load, trip their internal breaker repeatedly, and shorten the life of downstream control components.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power before servicing. Tools needed: multimeter, flathead and Phillips screwdrivers, wire nuts or quick-connects. Verify 24V output after installation before restoring full power. Label all wiring prior to disconnecting the old unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects. Orders placed before cutoff ship the same business day from our stocked warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed for the Carrier \u003cstrong\u003eC48A502551\u003c\/strong\u003e packaged unit. Always verify your unit's control voltage requirements on the data plate or wiring diagram before ordering. If you're unsure of fitment, our parts team is available to confirm compatibility before you buy — same-day shipping means you're back up and running fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909736157555,"sku":"CARRIE-C48A502551-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909736190323,"sku":"CARRIE-C48A502551-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_4342d2e7-b91d-45c7-af8d-341d54894b2e.jpg?v=1782940169","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c48a502551-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}