{"product_id":"carrier-ha1bjx036000aaaa-transformer-h4oyjb","title":"OEM Carrier Transformer 40VA 120V\/24V for HA1BJX036000AAAA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model HA1BJX036000AAAA\u003c\/h1\u003e\u003cp\u003eThis OEM replacement transformer (part# \u003cstrong\u003eHT01AW229\u003c\/strong\u003e) is the factory-specified step-down transformer for the \u003cstrong\u003eCarrier HA1BJX036000AAAA\u003c\/strong\u003e split-system unit. The transformer converts 120V line voltage to the 24V AC signal that powers the entire control circuit — including the thermostat, contactor coil, and safety switches. When it fails, nothing responds: the thermostat goes blank, the system won't call for heating or cooling, and no components energize. A failed transformer is one of the most commonly misdiagnosed HVAC problems because the symptoms mimic a bad thermostat or dead control board.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | Class 2 rated | Factory-matched output impedance for stable control voltage under load\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers (HT01AW229) are wound to Carrier's exact VA and voltage tolerances, ensuring reliable coil pull-in for the contactor and consistent board logic voltage. Generic transformers can sag under load, causing intermittent lockouts and nuisance fault codes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the breaker before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Verify 0V at primary terminals before touching wiring. Photograph all connections before removal. Reconnect secondary (24V) leads first, then primary.\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 Engineered specifically for the Carrier \u003cstrong\u003eHA1BJX036000AAAA\u003c\/strong\u003e (3-ton) split-system. Always confirm your existing transformer's VA rating and primary\/secondary voltages on the unit's wiring diagram before ordering — do not upsize VA without verifying board compatibility. Need fitment confirmation? Our HVAC parts specialists verify compatibility before you buy.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909363224947,"sku":"CARRIE-HA1BJX036000AAAA-TRANSFORMER-HT01AW229","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909363257715,"sku":"CARRIE-HA1BJX036000AAAA-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_a3bd0e4c-51dd-4a25-8f6b-db7529bdd8cc.jpg?v=1782941508","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ha1bjx036000aaaa-transformer-h4oyjb","provider":"National HVAC Parts","version":"1.0","type":"link"}