{"product_id":"carrier-ha1ajx030000abaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V\/24V for HA1AJX030000ABAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01AW229 for Model HA1AJX030000ABAA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part number \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier HA1AJX030000ABAA\u003c\/strong\u003e air handler. The transformer steps down line voltage — typically 120V primary — to 24V secondary power, energizing the low-voltage control circuit that operates your thermostat, relay coils, and all safety controls. When this transformer fails, the entire control circuit goes dead: the thermostat loses power, the system will not respond to any call for heating or cooling, and nothing works. It is one of the first components to check during a complete system no-response diagnostic.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Factory OEM part number HT01AW229 | Direct drop-in replacement with matched wiring terminations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM unit is wound and rated to exact Carrier factory specifications, ensuring proper VA capacity to handle all downstream control loads without overheating or sagging voltage — a common failure mode with undersized aftermarket transformers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power to the unit before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after installation). Photograph existing wiring connections before removal. Primary and secondary leads must be correctly identified and connected.\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\u003eHA1AJX030000ABAA\u003c\/strong\u003e air handler. Confirm your existing transformer's VA rating and primary\/secondary voltage from your unit's data plate or wiring diagram before ordering to ensure a proper match. Our parts specialists are available to verify fitment before you buy — order with confidence and get back up and running today.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909370138995,"sku":"CARRIE-HA1AJX030000ABAA-TRANSFORMER-HT01AW229","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909370171763,"sku":"CARRIE-HA1AJX030000ABAA-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_78eefd8f-76db-40ad-8214-7ea00f663138.jpg?v=1782941483","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ha1ajx030000abaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}