{"product_id":"carrier-fk4cnf002000agaa-transformer-h3hww2","title":"OEM Carrier Transformer 40VA 120V\/24V for FK4CNF002000AGAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01CN236 for Model FK4CNF002000AGAA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part# \u003cstrong\u003eHT01CN236\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier FK4CNF002000AGAA\u003c\/strong\u003e air handler. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, contactor coil, and every other low-voltage component in the system. When this transformer fails, absolutely nothing responds — the thermostat goes blank, the system won't call for heating or cooling, and no fault codes appear because the control board itself has lost power. If you've already ruled out a tripped breaker and a blown fuse, this transformer is the next component to test with a multimeter.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01CN236 | Factory-matched to Carrier FK4CNF002000AGAA air handler\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and potted to Carrier's exact VA rating and thermal protection specs. Undersized or off-tolerance generic transformers can overheat, blow the low-voltage fuse repeatedly, or damage sensitive control boards over time.\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, needle-nose pliers, wire nuts or spade connectors, and a multimeter to confirm output voltage after installation. Label all wires before removing the old unit.\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 3 PM local time.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed specifically for the Carrier \u003cstrong\u003eFK4CNF002000AGAA\u003c\/strong\u003e fan coil\/air handler. Always verify your existing transformer's VA rating and primary\/secondary voltages on the data plate or wiring diagram before ordering. Our fitment team is available to confirm compatibility before you purchase — no guesswork required.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909499703667,"sku":"CARRIE-FK4CNF002000AGAA-TRANSFORMER-HT01CN236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909499736435,"sku":"CARRIE-FK4CNF002000AGAA-TRANSFORMER-HT01CN236-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-HT01CN236_edf8dc34-89a3-4ef6-b1ba-165f05c62e23.jpg?v=1782941083","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fk4cnf002000agaa-transformer-h3hww2","provider":"National HVAC Parts","version":"1.0","type":"link"}