{"product_id":"carrier-gb1aav024035aaja-transformer-h2usbz","title":"OEM Carrier Transformer 40VA 120V-24V for GB1AAV024035AAJA","description":"\u003ch1\u003eOEM Carrier Control Circuit Transformer 40VA for Model GB1AAV024035AAJA\u003c\/h1\u003e\u003cp\u003eThis OEM control circuit transformer (part number \u003cstrong\u003eHT01BC116\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier GB1AAV024035AAJA\u003c\/strong\u003e fan coil unit. The transformer steps line voltage (120V) down to 24V AC to power the low-voltage control circuit — including the thermostat, control board, and all relay coils. When the transformer fails, the entire system goes silent: no thermostat response, no contactor pull-in, and no call for heating or cooling. If you're troubleshooting a completely unresponsive system and the breaker is good, a failed transformer is one of the first components to test.\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 HT01BC116 | Factory-matched output for full control circuit stability\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers maintain precise 24V output under load, protecting sensitive control boards from voltage fluctuation. Generic units with undersized VA ratings can sag under demand, causing erratic thermostat behavior and premature board failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Always shut off power at the breaker and verify zero voltage with a multimeter before handling. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade connectors. Photograph all wiring before disconnecting terminals.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In-stock units ship same business day from our warehouse when ordered before 3 PM local time.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed specifically for the Carrier \u003cstrong\u003eGB1AAV024035AAJA\u003c\/strong\u003e fan coil unit. Confirm your existing transformer's VA rating and primary\/secondary voltages on the unit's data plate before ordering. Our parts team is available to verify fitment — reach out before you buy if you have any questions.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909437673843,"sku":"CARRIE-GB1AAV024035AAJA-TRANSFORMER-HT01BC116","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909437706611,"sku":"CARRIE-GB1AAV024035AAJA-TRANSFORMER-HT01BC116-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-HT01BC116_a6fb3981-b2ca-40ee-89dd-f1395901a33e.jpg?v=1782939795","url":"https:\/\/nationalhvacparts.com\/products\/carrier-gb1aav024035aaja-transformer-h2usbz","provider":"National HVAC Parts","version":"1.0","type":"link"}