{"product_id":"carrier-hb1ajx048000aaaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V-24V for HB1AJX048000AAAA","description":"\u003ch1\u003eOEM Carrier Transformer 40VA 120V to 24V Control Circuit for Model HB1AJX048000AAAA\u003c\/h1\u003e\u003cp\u003eThis OEM replacement transformer (part number \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) is the factory-specified step-down transformer for the \u003cstrong\u003eCarrier HB1AJX048000AAAA\u003c\/strong\u003e packaged unit. The transformer converts 120V line voltage to the 24V AC signal that powers your thermostat, control board, and all low-voltage switching circuits. When this component fails, the entire control circuit goes dead — the thermostat goes blank, the system stops responding to calls for heating or cooling, and no contactors or relays will energize. A failed transformer is one of the most common causes of a completely unresponsive HVAC system.\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 HT01AW229 | Factory-matched windings and insulation class\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM transformer is wound to Carrier's exact VA rating and insulation specifications. Generic alternatives frequently run undersized VA ratings, causing overheating and premature failure — especially in systems with multiple 24V accessories such as humidifiers or zone boards.\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, multimeter (to confirm 24V output after install). Always label or photograph low-voltage wiring connections before disconnecting the old unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects. In-stock and ships same business day from our climate-controlled warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered specifically for the \u003cstrong\u003eCarrier HB1AJX048000AAAA\u003c\/strong\u003e packaged unit. Confirm your existing transformer's primary voltage (120V), secondary voltage (24V), and VA rating on the unit data plate before ordering. If you are unsure of fitment, our HVAC parts specialists verify compatibility before you buy — no guesswork required. Order today and get same-day shipping on in-stock parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909350740339,"sku":"CARRIE-HB1AJX048000AAAA-TRANSFORMER-HT01AW229","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909350773107,"sku":"CARRIE-HB1AJX048000AAAA-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_678d05f2-517b-4df8-8ca9-86f024d74871.jpg?v=1782939900","url":"https:\/\/nationalhvacparts.com\/products\/carrier-hb1ajx048000aaaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}