{"product_id":"carrier-fb4cnp036l00aaaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V-24V for FB4CNP036L00AAAA","description":"\u003ch1\u003eOEM Carrier Transformer 40VA 120V–24V for Model FB4CNP036L00AAAA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier FB4CNP036L00AAAA\u003c\/strong\u003e fan coil air handler. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, and all low-voltage switching circuits. When the transformer fails, the entire control circuit goes dark — the thermostat becomes unresponsive, the system won't heat or cool, and no error codes will display because the board itself has no power. A failed transformer is often misdiagnosed as a thermostat or control board issue, making it a critical first-check component.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | Primary: 120V AC | Secondary: 24V AC | Class 2 insulated | Matches factory-specified HT01CN241 exactly\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and insulated to Carrier's exact VA and thermal specifications. Generic units may be under-rated for VA load, leading to overheating, nuisance tripping, or premature failure — especially under multi-zone or communicating thermostat loads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Note wire colors and terminal labels before disconnecting the old unit. Verify 24V output with a multimeter after installation 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 for the Carrier \u003cstrong\u003eFB4CNP036L00AAAA\u003c\/strong\u003e fan coil air handler. Verify your existing transformer is rated 40VA 120V\/24V by checking the data label on the transformer body before ordering. If your control board or thermostat still shows no power after replacement, also check for a shorted low-voltage wire causing repeated transformer failure. Our fitment team is available to confirm compatibility before you order — reach out before placing your order if you have any questions.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909533684083,"sku":"CARRIE-FB4CNP036L00AAAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909533716851,"sku":"CARRIE-FB4CNP036L00AAAA-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_31bc2aef-260a-48c0-bf0c-079e89d7e5ec.jpg?v=1782939545","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fb4cnp036l00aaaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}