{"product_id":"carrier-upflow125hcu12b-transformer-h3hvc4","title":"OEM Carrier Furnace Transformer 40VA 120V\/24V — UPFLOW125HCU12B","description":"\u003ch1\u003eOEM Carrier Furnace Transformer 40VA 120V to 24V for Model UPFLOW125HCU12B\u003c\/h1\u003e\u003cp\u003eThis OEM Carrier transformer (part #HT01CN001) is the factory-specified replacement for the \u003cstrong\u003eCarrier UPFLOW125HCU12B\u003c\/strong\u003e upflow furnace. The transformer steps down 120V line voltage to a safe 24V (with a 12V tap) to power the low-voltage control circuit — including the thermostat, ignition board, and all 24V relay logic. When this transformer fails, the entire control circuit loses power: the thermostat goes blank, the furnace won't respond to any command, and you may detect buzzing or humming from the transformer housing itself.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA capacity | 120V primary | 12V\/24V dual secondary | OEM part #HT01CN001 | Replaces legacy part numbers HT01BJ115, 19EA41612, 19EA42612\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound to exact factory VA and voltage specifications, ensuring full 24V output under load. Undersized or off-tolerance aftermarket units can cause erratic board behavior, nuisance lockouts, and premature control board failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off all power at the breaker before proceeding. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to verify 24V output after install). Label or photograph all wiring connections before disconnecting. The transformer is typically mounted to the furnace cabinet with one or two screws and connects via quick-disconnect terminals.\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 for the Carrier \u003cstrong\u003eUPFLOW125HCU12B\u003c\/strong\u003e upflow gas furnace. Verify the part number on your existing transformer's label before ordering — input voltage (120V), output voltage (24V\/12V), and VA rating (40VA) must match. Our HVAC parts specialists are available to confirm fitment before you purchase. Order now for same-day dispatch.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640231121267,"sku":"CARRIE-UPFLOW125HCU12B-TRANSFORMER-HT01CN001","price":353.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640231154035,"sku":"CARRIE-UPFLOW125HCU12B-TRANSFORMER-HT01CN001-GEN","price":311.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01CN001_2d68bb5d-ae91-4a7b-8d34-c45fc1165d97.jpg?v=1775031855","url":"https:\/\/nationalhvacparts.com\/products\/carrier-upflow125hcu12b-transformer-h3hvc4","provider":"National HVAC Parts","version":"1.0","type":"link"}