{"product_id":"carrier-hb1bjx042000aaaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V\/24V for HB1BJX042000AAAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model HB1BJX042000AAAA\u003c\/h1\u003e\u003cp\u003eThis is the OEM factory-specified replacement transformer (part number \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) for the \u003cstrong\u003eCarrier HB1BJX042000AAAA\u003c\/strong\u003e unit. The transformer steps line voltage (120V) down to the 24V signal used by the control board, thermostat, and all low-voltage components. When this part fails, the entire control circuit goes dead — your thermostat loses power, the system won't respond to any calls for heating or cooling, and in some cases a blown fuse or tripped breaker on the secondary side is the first sign of trouble.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | Primary: 120V | Secondary: 24V | OEM part number HT01AW229 | Factory-matched for Carrier control circuit requirements\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and rated to exact factory VA tolerances, preventing nuisance fuse failures and ensuring stable 24V output under full control-circuit load. Generic alternatives may be under-rated, causing voltage sag and intermittent lockouts.\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, wire nuts or spade connectors, multimeter to verify 24V output after installation. Always label or photograph existing wiring before disconnecting.\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 a direct OEM replacement for the Carrier \u003cstrong\u003eHB1BJX042000AAAA\u003c\/strong\u003e. Confirm your existing transformer's primary voltage (120V), secondary voltage (24V), and VA rating on the unit's data plate or wiring diagram before ordering. Need help confirming fitment? Our HVAC parts specialists verify compatibility before you buy — ships same day.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909348217203,"sku":"CARRIE-HB1BJX042000AAAA-TRANSFORMER-HT01AW229","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909348249971,"sku":"CARRIE-HB1BJX042000AAAA-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_20d26d68-c406-4491-b694-e222e37c7958.jpg?v=1782941564","url":"https:\/\/nationalhvacparts.com\/products\/carrier-hb1bjx042000aaaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}