{"product_id":"carrier-fx4dnf043010aaaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V-24V for FX4DNF043010AAAA","description":"\u003ch1\u003eOEM Carrier Transformer 40VA 120V to 24V for Model FX4DNF043010AAAA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier FX4DNF043010AAAA\u003c\/strong\u003e fan coil air handler. The transformer steps down line voltage from 120V to the 24V signal required by the control board, thermostat, and all low-voltage control circuit components. When this transformer fails, the entire control circuit loses power — symptoms include a completely unresponsive thermostat, no system startup whatsoever, and a blown 3-amp fuse on the control board. If your system shows no signs of life even when power is confirmed at the unit, this transformer is the most common culprit.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 120V primary | 24V secondary | 40VA rated | 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 OEM transformers are wound to exact VA and voltage tolerances required by Carrier's control board. Undersized or off-tolerance generic units can cause nuisance tripped fuses, control board brownouts, or premature contactor coil wear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Shut off all power to the air handler before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, needle-nose pliers, and a multimeter to verify output voltage after installation. Label all low-voltage wires before disconnecting. The transformer mounts to the control panel bracket with two screws and uses spade or wire-nut connections.\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\u003eFX4DNF043010AAAA\u003c\/strong\u003e fan coil air handler. Always verify your unit's control circuit voltage and VA requirement on the data plate or wiring diagram before ordering. Our HVAC parts specialists are available to confirm fitment — don't guess on a control circuit component. Order today and receive same-day shipping on all in-stock parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909474341235,"sku":"CARRIE-FX4DNF043010AAAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909474374003,"sku":"CARRIE-FX4DNF043010AAAA-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_5be4f750-01c5-4ad8-9d0b-178203c7ac87.jpg?v=1782939689","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fx4dnf043010aaaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}