{"product_id":"carrier-c4850c48zn035500-transformer-h302a1","title":"OEM Carrier 40VA 120V to 24V Control Transformer for C4850C48ZN035500 | National HVAC Parts","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer HT01BD236 for Model C4850C48ZN035500\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part number \u003cstrong\u003eHT01BD236\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003eCarrier C4850C48ZN035500\u003c\/strong\u003e packaged unit. The transformer steps down 120V line voltage to the 24V signal required by your thermostat, control board, contactor coil, and all low-voltage safety circuits. When the transformer fails, the entire control circuit goes dead — the thermostat goes blank, the system won't respond to any command, and nothing turns on. It is often the first component to diagnose when a unit shows zero low-voltage activity.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e Primary 120V AC | Secondary 24V AC | 40VA rated | OEM part number HT01BD236 | Factory-matched impedance and thermal protection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This OEM transformer meets exact Carrier factory specifications for VA rating, insulation class, and thermal cutout thresholds. Generic transformers often run undersized VA ratings, causing premature failure or nuisance tripping under normal load — especially in systems with multiple accessories drawing from the 24V circuit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 2\/5\u003c\/strong\u003e — Shut off all power at the breaker and disconnect switch before starting. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, wire stripper, multimeter to confirm 0V before touching wiring. Label or photograph all low-voltage wiring connections before removal.\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 specifically for the \u003cstrong\u003eCarrier C4850C48ZN035500\u003c\/strong\u003e packaged unit. Verify your existing transformer's primary\/secondary voltage and VA rating on the data plate before ordering. If you have questions about fitment or want us to verify compatibility before you buy, our HVAC parts specialists are standing by. Order today and your part ships same business day.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62909859332467,"sku":"CARRIE-C4850C48ZN035500-TRANSFORMER-HT01BD236","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62909859365235,"sku":"CARRIE-C4850C48ZN035500-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_7c2b5d30-50e7-4489-a0c0-0046aa37814d.jpg?v=1782899081","url":"https:\/\/nationalhvacparts.com\/products\/carrier-c4850c48zn035500-transformer-h302a1","provider":"National HVAC Parts","version":"1.0","type":"link"}