{"product_id":"carrier-c48a902064-transformer-h301d7","title":"OEM Carrier Transformer 40VA 120V\/24V for C48A902064 — HT01BD702","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 120V\/24V for Model C48A902064\u003c\/h1\u003e\u003cp\u003eThis is the OEM factory-replacement control transformer (part number \u003cstrong\u003eHT01BD702\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier C48A902064\u003c\/strong\u003e packaged unit. The transformer steps down line voltage (120V) to the 24V signal voltage that powers your thermostat, control board, contactor coil, and all low-voltage control circuitry. When this transformer fails, the entire control circuit goes dead — the thermostat displays nothing, the system won't respond to any calls for heating or cooling, and no error codes are generated because the board itself has no power. Replacing a failed transformer is one of the first diagnostic steps any technician takes when a unit is completely unresponsive.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V | Secondary: 24V | Factory-matched OEM tolerances | Terminals compatible with OEM wiring harness on C48A902064\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and insulated to Carrier's exact specifications, ensuring stable 24V output under load. Generic units often suffer from voltage sag under peak demand, causing nuisance lockouts and intermittent control board faults.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the disconnect box and verify zero voltage with a multimeter before touching any wiring. Tools needed: flathead and Phillips screwdrivers, multimeter, needle-nose pliers. Label all wires before disconnecting. Replace the transformer with power off and confirm 24V output before closing the panel.\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 specifically for the \u003cstrong\u003eCarrier C48A902064\u003c\/strong\u003e packaged unit using OEM part number HT01BD702. Always verify your unit's data plate and existing transformer VA and voltage ratings match before ordering. Our fitment team is available to confirm compatibility before you buy — order with confidence and get your system back online fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909720494451,"sku":"CARRIE-C48A902064-TRANSFORMER-HT01BD702","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909720527219,"sku":"CARRIE-C48A902064-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_a80785bc-5c97-4bfe-9d62-5c4e0afdca5c.jpg?v=1782940301","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c48a902064-transformer-h301d7","provider":"National HVAC Parts","version":"1.0","type":"link"}