{"product_id":"carrier-fx4cnf042000aaaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V\/24V for FX4CNF042000AAAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model FX4CNF042000AAAA\u003c\/h1\u003e\u003cp\u003eThis OEM replacement transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) is the factory-specified step-down transformer for the \u003cstrong\u003eCarrier FX4CNF042000AAAA\u003c\/strong\u003e fan coil unit. It converts 120V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage system controls. When this transformer fails, the entire control circuit goes dead — your thermostat will appear unresponsive, the system won't call for heating or cooling, and no error codes will display because the board itself has lost power.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | OEM part number HT01CN241 | Factory-matched to Carrier FX4CNF042000AAAA control circuit requirements\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 tripping, blown fuses, and premature control board failure — costing far more than the transformer itself.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off all power to the unit at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter to verify 24V output after install. Photograph all wiring connections before disconnecting the old transformer.\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\u003eFX4CNF042000AAAA\u003c\/strong\u003e fan coil unit. Verify your existing transformer's VA rating and primary\/secondary voltages on the data plate before ordering. If you're unsure of fitment, our HVAC parts specialists are available to confirm compatibility before you buy. Order today and get same-day shipping on all in-stock parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909482303859,"sku":"CARRIE-FX4CNF042000AAAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909482336627,"sku":"CARRIE-FX4CNF042000AAAA-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_0cc30eab-5f1c-470d-ba84-ea9c4a3c219f.jpg?v=1782941188","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fx4cnf042000aaaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}