{"product_id":"carrier-c4850c48ay03651-transformer-h302a1","title":"OEM Carrier Transformer 40VA 120V\/24V for C4850C48AY03651","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model C4850C48AY03651\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part# \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier C4850C48AY03651\u003c\/strong\u003e packaged unit. The transformer steps down 120V line voltage to the 24V signal required by your thermostat, contactor coil, and all low-voltage control components. When the transformer fails, the entire control circuit goes dark — your thermostat displays nothing, the system won't respond to calls for heating or cooling, and no staging or safety functions operate. Replacing it with the correct OEM part restores reliable, factory-spec control voltage immediately.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | 120V primary \/ 24V secondary | Class 2 transformer | OEM part number HT01BD236 | Factory-matched for Carrier C4850C48AY03651\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM unit meets Carrier's exact VA rating and insulation class. Undersized or generic transformers can overheat under full control-circuit load, causing nuisance failures and potential board damage downstream.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Shut off all power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, wire stripper, multimeter. Label all low-voltage wiring before removing the old transformer to ensure correct reconnection.\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 Designed specifically for the Carrier \u003cstrong\u003eC4850C48AY03651\u003c\/strong\u003e packaged unit. Always verify your existing transformer's VA rating and primary\/secondary voltages on the unit data plate before ordering. Our fitment team is available to confirm compatibility prior to purchase — order with confidence and get your system back online today.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909882237299,"sku":"CARRIE-C4850C48AY03651-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909882270067,"sku":"CARRIE-C4850C48AY03651-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_01cf47cf-9a66-43bb-9c26-b4b956065c9f.jpg?v=1782940049","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c48ay03651-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}