{"product_id":"carrier-fb4cnfs24l00adaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V\/24V for FB4CNFS24L00ADAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01CN241 for Model FB4CNFS24L00ADAA\u003c\/h1\u003e\u003cp\u003eThis OEM replacement transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) is the factory-specified control circuit transformer for the \u003cstrong\u003eCarrier FB4CNFS24L00ADAA\u003c\/strong\u003e fan coil air handler. The transformer steps down line voltage from 120V to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching circuits. When the transformer fails, nothing works — the thermostat goes dark, the system won't respond to calls for heating or cooling, and the control board loses all power. A failed transformer is often confirmed by measuring 0V at the secondary terminals (R and C on the control board) with a multimeter while line voltage is confirmed at the primary.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01CN241 | Factory-matched output for Carrier low-voltage control circuits\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This is a genuine OEM Carrier transformer manufactured to exact VA and voltage tolerances. Generic transformers with loose VA ratings can under-power control boards, causing nuisance lockouts, intermittent thermostat dropouts, and premature board failure — costing far more than the part itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off power at the breaker and verify zero voltage before disconnecting. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or quick-connect terminals. Photograph all wiring connections before removing the old transformer. Primary wires carry 120V — treat with appropriate care.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects. In-stock units ship same business day when ordered before cutoff.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered as a direct OEM replacement for the Carrier \u003cstrong\u003eFB4CNFS24L00ADAA\u003c\/strong\u003e fan coil air handler. Verify your existing transformer's VA rating and primary\/secondary voltages on the unit data plate or component label before ordering. Our HVAC parts specialists are available to confirm fitment — order with confidence.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909534896499,"sku":"CARRIE-FB4CNFS24L00ADAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909534929267,"sku":"CARRIE-FB4CNFS24L00ADAA-TRANSFORMER-HT01CN241-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-HT01CN241_c3dd1363-bdf9-4ff7-ac21-016679604481.jpg?v=1782940933","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fb4cnfs24l00adaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}