{"product_id":"carrier-fb4bnf018005aaaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V\/24V for FB4BNF018005AAAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Circuit Transformer for Model FB4BNF018005AAAA\u003c\/h1\u003e\u003cp\u003eThis OEM Carrier transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eFB4BNF018005AAAA\u003c\/strong\u003e fan coil air handler. The transformer steps line voltage (120V) down to 24V AC to power the low-voltage control circuit, including the thermostat, contactor coil, and control board. When it fails, the entire control circuit goes dead — your thermostat goes blank, the system won't respond to any calls for heating or cooling, and no components will energize. A failed transformer is often one of the first things to check when a system appears completely unresponsive.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary input | 24V secondary output | Factory OEM part number HT01CN241 | Direct plug-and-play replacement with original mounting footprint\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e The OEM HT01CN241 transformer is wound and insulated to Carrier's exact specifications, ensuring proper VA capacity and long-term thermal stability. Generic transformers may be undersized in VA rating, leading to overheating, nuisance tripping of the internal fuse, or premature failure that can damage downstream control boards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all wire connections before removal. Verify 24V output with a multimeter after installation before restoring full power.\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 Carrier \u003cstrong\u003eFB4BNF018005AAAA\u003c\/strong\u003e fan coil air handler. Always verify your existing transformer's primary\/secondary voltage and VA rating on the unit's data plate before ordering. Our parts specialists are available to confirm fitment — reach out before you order if you have any questions. Order today and receive same-day shipping on in-stock parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909541548403,"sku":"CARRIE-FB4BNF018005AAAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909541581171,"sku":"CARRIE-FB4BNF018005AAAA-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_bdaf6e42-afc8-45d4-af58-f308ef6eccf2.jpg?v=1782940894","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fb4bnf018005aaaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}