{"product_id":"carrier-c4850c50aj05051-transformer-h302a1","title":"OEM Carrier 40VA 120V to 24V Control Transformer for C4850C50AJ05051 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model C4850C50AJ05051 — Part# HT01BD236\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part# \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier C4850C50AJ05051\u003c\/strong\u003e packaged unit. The transformer steps down line voltage (120V) to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching circuits. When this component fails, the entire control circuit goes dark — your thermostat shows a blank screen, the system refuses to respond to any call for heating or cooling, and no fault codes are generated because the board itself has no power. It is often the first component to check when nothing works at all.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary → 24V secondary | Factory-matched impedance and core construction | Class 2 output for low-voltage control circuits | OEM part number HT01BD236\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound to exact factory VA and voltage tolerances, protecting downstream control boards from voltage fluctuations. Generic units frequently run under-rated VA, causing overheating, nuisance tripping, and premature control board failure — costing far more than the transformer itself.\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. Confirm primary and secondary voltages with a multimeter after installation before restoring full power. Label all wires before disconnecting the old unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects in materials and workmanship. Ships 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\u003eC4850C50AJ05051\u003c\/strong\u003e packaged unit. Verify your existing transformer's VA rating, primary voltage, and secondary voltage on the unit's data plate or wiring diagram before ordering — mismatched VA ratings can damage control boards. Our parts specialists are available to confirm fitment before you purchase. \u003cstrong\u003eOrder today and your part ships the same business day.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909836001651,"sku":"CARRIE-C4850C50AJ05051-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909836034419,"sku":"CARRIE-C4850C50AJ05051-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_195acd68-5825-4c53-8039-2ad8b85b39ac.jpg?v=1782899105","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c50aj05051-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}