{"product_id":"carrier-fx4dnf019005aaaa-transformer-h3hwwy","title":"OEM Carrier Transformer 40VA 120V-24V for FX4DNF019005AAAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01CN241 for Model FX4DNF019005AAAA\u003c\/h1\u003e\u003cp\u003eThis is the OEM factory-specified control transformer (part number \u003cstrong\u003eHT01CN241\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier FX4DNF019005AAAA\u003c\/strong\u003e fan coil air handler. The transformer steps down line voltage from 120V to 24V to power the low-voltage control circuit — including the thermostat, contactor coil, and any zone controls. When this transformer fails, the entire control system goes dark: your thermostat goes blank, the system makes no response to a call for cooling or heating, and a voltage check at the secondary terminals will read zero. It is one of the first components to test when diagnosing a completely unresponsive system.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | Factory OEM part number HT01CN241 | Compact chassis-mount design for air handler installation\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM transformer is wound and tested to Carrier's exact VA and voltage specifications. Generic transformers frequently underperform at rated VA, causing nuisance tripping of the secondary fuse and premature control board failures under normal load.\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. Label all 24V low-voltage wires before disconnecting. Confirm 0V at primary terminals before handling. A straightforward swap for any experienced DIYer or HVAC technician.\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 as the direct OEM replacement for the Carrier \u003cstrong\u003eFX4DNF019005AAAA\u003c\/strong\u003e fan coil air handler. Always verify your existing transformer's VA rating and primary\/secondary voltages on the unit data plate before ordering to confirm fitment. Have a question about compatibility? Our HVAC parts specialists verify fitment before you buy — reach out before placing your order.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909479190899,"sku":"CARRIE-FX4DNF019005AAAA-TRANSFORMER-HT01CN241","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909479223667,"sku":"CARRIE-FX4DNF019005AAAA-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_fec0d806-7c04-4bff-b73d-b9b5f8f4e695.jpg?v=1782939666","url":"https:\/\/nationalhvacparts.com\/products\/carrier-fx4dnf019005aaaa-transformer-h3hwwy","provider":"National HVAC Parts","version":"1.0","type":"link"}