{"product_id":"carrier-c4850c48zn035200-transformer-h302a1","title":"OEM Carrier 40VA 120V to 24V Control Transformer for C4850C48ZN035200 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model C4850C48ZN035200\u003c\/h1\u003e\u003cp\u003eThis OEM step-down transformer (part# \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier C4850C48ZN035200\u003c\/strong\u003e packaged unit. The transformer converts 120V line voltage to the 24V AC signal that powers your thermostat, control board, contactor coils, and all low-voltage safety circuits. When it fails, the entire control circuit goes dark — the thermostat shows no response, the system won't initiate a heating or cooling call, and nothing works regardless of thermostat settings. A failed transformer is often misdiagnosed as a bad control board, making this a critical first-check component.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V AC | Secondary: 24V AC | OEM Part# HT01BD236 | Factory wire leads for direct reconnection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound to exact VA and voltage tolerances required by the Carrier C4850C48ZN035200 control circuit. Undersized or off-tolerance generic transformers can overheat, blow fuses repeatedly, or cause nuisance lockouts that are difficult to diagnose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the disconnect box and verify zero voltage with a multimeter before beginning. Tools needed: flathead and Phillips screwdrivers, wire nuts or terminal connectors, multimeter. Label or photograph all wire connections before removal. Check for a blown 3A or 5A control fuse on the board — a shorted transformer often takes the fuse with it.\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 for the Carrier \u003cstrong\u003eC4850C48ZN035200\u003c\/strong\u003e packaged unit. Verify your existing transformer's VA rating and primary\/secondary voltages on the data plate or wiring diagram before ordering. If you're unsure of fitment, our parts specialists can verify compatibility before you purchase — same-day shipping available on all in-stock OEM parts.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909859430771,"sku":"CARRIE-C4850C48ZN035200-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909859463539,"sku":"CARRIE-C4850C48ZN035200-TRANSFORMER-HT01BD236-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-HT01BD236_369e935b-b661-4785-b795-72fbda48475d.jpg?v=1782899079","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c48zn035200-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}