{"product_id":"carrier-c48a904064-transformer-h301d7","title":"OEM Carrier Transformer 40VA 120V\/24V for C48A904064 — HT01BD702","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 120V\/24V for Model C48A904064 — Part HT01BD702\u003c\/h1\u003e\u003cp\u003eThis OEM replacement control transformer (part number \u003cstrong\u003eHT01BD702\u003c\/strong\u003e) is the factory-specified unit for the \u003cstrong\u003eCarrier C48A904064\u003c\/strong\u003e packaged system. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, contactor coil, and all low-voltage controls. When it fails, the result is total control circuit loss — your thermostat goes blank, the system won't respond to any call for heating or cooling, and nothing works. A failed transformer is often misdiagnosed as a bad thermostat or control board, making correct identification critical before replacing costlier components.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Class 2 control transformer | Direct OEM replacement for part number HT01BD702\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound to exact VA and impedance specifications for your Carrier unit. Undersized or off-spec generic transformers can blow fuses repeatedly or fail to sustain 24V under full control circuit load, leading to nuisance lockouts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Test primary voltage before install and verify 24V output after. Always label wires before disconnecting old transformer leads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. Orders placed before cutoff ship 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\u003eC48A904064\u003c\/strong\u003e packaged unit. Verify your existing transformer's VA rating and primary\/secondary voltages on the unit data plate or wiring diagram before ordering to confirm fitment. Our parts specialists are available to verify compatibility before you purchase — no guesswork required.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909719314803,"sku":"CARRIE-C48A904064-TRANSFORMER-HT01BD702","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909719347571,"sku":"CARRIE-C48A904064-TRANSFORMER-HT01BD702-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-HT01BD702_e01ac8db-a613-43bf-b1fe-e8c816e10f23.jpg?v=1782940313","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c48a904064-transformer-h301d7","provider":"National HVAC Parts","version":"1.0","type":"link"}