{"product_id":"carrier-py3pna042090ab-transformer-h30291","title":"OEM Carrier Transformer 40VA 208\/240V–24V for PY3PNA042090AB","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 208\/240V to 24V for Model PY3PNA042090AB\u003c\/h1\u003e\u003cp\u003eThis OEM Carrier transformer (part #HT01BD209) is the factory-specified replacement for the \u003cstrong\u003eCarrier PY3PNA042090AB\u003c\/strong\u003e packaged unit. The transformer steps down 208\/240V line voltage to the 24V control-circuit voltage required to power your thermostat, contactor coil, and all low-voltage safety controls. When this transformer fails, the entire control circuit goes dark — no thermostat response, no ignition sequence, and no condenser contactor pull-in. It is often the first component to check when a system appears completely unresponsive despite line voltage being present at the unit.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e Input 208\/240V | Output 24V | 40VA power rating | 50\/60Hz | OEM part number HT01BD209\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e The OEM Carrier transformer is wound to exact factory VA and impedance tolerances, ensuring stable 24V output under full control-circuit load. Generic units with loose VA ratings can cause nuisance tripping of the transformer's internal overload or undervolt conditions on the control board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Always disconnect line voltage at the disconnect box and confirm zero voltage with a multimeter before touching wiring. Note wire colors and terminal labels before removing the old transformer. Tools needed: flathead and Phillips screwdriver, multimeter, wire nuts or terminal connectors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before cutoff.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Verified fit for Carrier model \u003cstrong\u003ePY3PNA042090AB\u003c\/strong\u003e. Always confirm input voltage (208V or 240V) on your unit's data plate matches the transformer's primary tap before installing. Have a question about fitment? Our HVAC parts team verifies compatibility before you order — reach out today and get your system back online fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640384999795,"sku":"CARRIE-PY3PNA042090AB-TRANSFORMER-HT01BD209","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640385032563,"sku":"CARRIE-PY3PNA042090AB-TRANSFORMER-HT01BD209-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-HT01BD209_023e3074-9fee-4bfe-a9f8-9d93429af41f.jpg?v=1782942406","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py3pna042090ab-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}