{"product_id":"carrier-ha1ajx018000abaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V\/24V for HA1AJX018000ABAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model HA1AJX018000ABAA\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part# \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier HA1AJX018000ABAA\u003c\/strong\u003e air handler. The transformer steps down 120V line voltage to 24V AC to power the low-voltage control circuit — including the thermostat, contactor coil, and control board. When it fails, the entire control system goes dark: the thermostat loses power, no calls for heating or cooling are processed, and the system will not operate at all. A failed transformer is often misdiagnosed as a thermostat or control board failure, making it one of the first components to verify during a no-power diagnostic.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | Primary: 120V AC | Secondary: 24V AC | OEM part number HT01AW229 | Factory-matched output for stable control circuit voltage\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 voltage tolerances. Undersized or off-tolerance generic units can cause nuisance tripping, board brownouts, and premature contactor coil failure — costing far more than the price difference.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off power at the disconnect and breaker before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or terminal connectors. Verify primary and secondary voltages with a multimeter after installation before restoring full system power.\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 3PM local time.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed as a direct OEM replacement for the \u003cstrong\u003eCarrier HA1AJX018000ABAA\u003c\/strong\u003e air handler. Always confirm the 40VA rating and 120V\/24V configuration against your unit's wiring diagram and data plate before ordering. Our parts specialists are available to verify fitment — order with confidence and get your system back online fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909371580787,"sku":"CARRIE-HA1AJX018000ABAA-TRANSFORMER-HT01AW229","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909371613555,"sku":"CARRIE-HA1AJX018000ABAA-TRANSFORMER-HT01AW229-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-HT01AW229_a03aeea0-3b15-4266-af25-815c8cb078e7.jpg?v=1782941477","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ha1ajx018000abaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}