{"product_id":"carrier-c4850c50z3040200-transformer-h302a1","title":"OEM Carrier Transformer 40VA 120V to 24V for C4850C50Z3040200 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model C4850C50Z3040200\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part number \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier C4850C50Z3040200\u003c\/strong\u003e packaged unit. The transformer steps down 120V line voltage to the 24V signal needed to power the control board, thermostat, contactor coil, and all low-voltage safety circuits. When this part fails, absolutely nothing responds — the thermostat goes dark, the system won't call for heating or cooling, and no error codes are generated because the control circuit has no power to report them.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | 120V primary \/ 24V secondary | Class 2 insulation | Direct OEM replacement for part number HT01BD236 | Mounts to existing bracket with standard wiring harness connections\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 control board. Undersized or off-tolerance generic units overheat under load, blow fuses repeatedly, and can damage downstream boards — a far more expensive repair.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off all power to the unit at the disconnect before beginning. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter, needle-nose pliers. Label and photograph all low-voltage wiring connections before removing the old transformer. Verify 24V output at secondary terminals before closing the panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects in materials and workmanship. Ships same business day from our climate-controlled warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered for the \u003cstrong\u003eCarrier C4850C50Z3040200\u003c\/strong\u003e packaged unit. Confirm your existing transformer's VA rating and primary\/secondary voltages on the unit data plate or wiring diagram before ordering. If you're unsure of fitment, our HVAC parts specialists verify compatibility before your order ships — no guesswork required.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909796680051,"sku":"CARRIE-C4850C50Z3040200-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909796712819,"sku":"CARRIE-C4850C50Z3040200-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_df71ab4a-7e23-481d-9856-34f75262c342.jpg?v=1782939021","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c50z3040200-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}