{"product_id":"carrier-u19x100u48b-transformer-h3hvc4","title":"OEM Carrier 40VA Transformer HT01CN001 for U19X100U48B","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01CN001 for Model U19X100U48B\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer is the factory-specified replacement for the \u003cstrong\u003eCarrier U19X100U48B\u003c\/strong\u003e packaged or split-system unit. The transformer steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, and all low-voltage switching circuits. When this component fails, the entire control circuit goes dark — symptoms include a completely blank thermostat, a control board with no indicator lights, or a system that won't respond to any call for heating or cooling despite power being present at the unit.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Factory-matched OEM replacement | Direct plug-in terminal connections for fast swap\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers from Carrier are wound to exact VA and voltage tolerances, ensuring stable 24V output under full control-circuit load. Generic alternatives may sag under load, causing intermittent lockouts, nuisance tripping of fuses, or premature control board failure.\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, needle-nose pliers, multimeter (to verify 24V output after install). Label or photograph all wiring connections before removal.\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 warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered as a direct OEM replacement for \u003cstrong\u003eCarrier model U19X100U48B\u003c\/strong\u003e. Always confirm primary voltage (120V) and VA rating on your existing unit's data plate or wiring diagram before ordering. Our HVAC parts specialists are available to verify fitment — order with confidence.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640247505267,"sku":"CARRIE-U19X100U48B-TRANSFORMER-HT01CN001","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640247538035,"sku":"CARRIE-U19X100U48B-TRANSFORMER-HT01CN001-GEN","price":30.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01CN001_080a0d4d-35a2-4107-9b8a-d539d3279c64.jpg?v=1775016640","url":"https:\/\/nationalhvacparts.com\/products\/carrier-u19x100u48b-transformer-h3hvc4","provider":"National HVAC Parts","version":"1.0","type":"link"}