{"product_id":"carrier-c48a402751-transformer-h302a1","title":"OEM Carrier Transformer 40VA 120V to 24V for C48A402751 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier Transformer 40VA 120V\/24V for Model C48A402751\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 C48A402751\u003c\/strong\u003e packaged unit. The control transformer steps down line voltage from 120V to 24V to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When it fails, nothing responds: the thermostat goes dark, relays won't energize, and the system is completely unresponsive despite power being present at the unit.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Factory-matched impedance and thermal protection | Replaces OEM part number HT01BD236\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM unit is wound to Carrier's exact VA rating and insulation class. Undersized or off-spec generic transformers can overheat, trip the internal fuse, or fail to sustain the 24V circuit under full relay load — causing intermittent lockouts that are difficult to diagnose.\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 terminals. Always confirm 24V output with a meter before reassembling the control panel. Check for shorted wiring in the low-voltage circuit before installing the new transformer to avoid repeat failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. 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 for the \u003cstrong\u003eCarrier C48A402751\u003c\/strong\u003e packaged unit. Verify the transformer VA rating and primary\/secondary voltages on your unit's wiring diagram or data plate before ordering. If you're unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you buy — order with confidence and get back up and running fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909744578931,"sku":"CARRIE-C48A402751-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909744611699,"sku":"CARRIE-C48A402751-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_22394ca3-411d-4b05-a80f-80c78ba44d2d.jpg?v=1782939205","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c48a402751-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}