{"product_id":"carrier-ph4zna042000aa-transformer-h30291","title":"OEM Carrier Control Transformer 40VA 208\/240V-24V — PH4ZNA042000AA","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 208\/240V to 24V for Model PH4ZNA042000AA\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer is the factory-specified replacement for the \u003cstrong\u003eCarrier PH4ZNA042000AA\u003c\/strong\u003e packaged HVAC unit. The transformer steps down 208\/240V line voltage to the 24V signal voltage that powers your thermostat, control board, contactors, and every other low-voltage component in the system. When this part fails, the entire control circuit goes dead — the unit will not respond to thermostat calls, and nothing will turn on. A failed transformer is one of the most common causes of a completely unresponsive HVAC system.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA capacity | 208\/240V primary input | 24V secondary output | 50\/60 Hz rated | OEM part number HT01BD209 | Also replaces HT01BD207, HT01CN232, and 9076-00\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and rated to exact factory tolerances, ensuring stable 24V output under all load conditions. Generic units may exhibit voltage sag under full load, causing erratic thermostat behavior or nuisance control board faults.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect all power before starting. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter. Photograph all wiring connections before removal. Verify 24V output at secondary terminals after installation before closing the cabinet.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. Ships same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Fits Carrier model \u003cstrong\u003ePH4ZNA042000AA\u003c\/strong\u003e packaged unit. Also compatible with select Bryant and Payne units using the same 40VA 208\/240V–24V transformer specification. Always verify your unit's data plate and existing transformer VA and voltage ratings before ordering. Questions about fitment? Our HVAC parts specialists confirm compatibility before you buy.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62641154589043,"sku":"CARRIE-PH4ZNA042000AA-TRANSFORMER-HT01BD209","price":87.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62641154621811,"sku":"CARRIE-PH4ZNA042000AA-TRANSFORMER-HT01BD209-GEN","price":77.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01BD209_d82a095c-3307-4e9d-a130-578d0eb20e62.jpg?v=1775025579","url":"https:\/\/nationalhvacparts.com\/products\/carrier-ph4zna042000aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}