{"product_id":"carrier-py3gna030040ab-transformer-h30291","title":"OEM Carrier Control Transformer 40VA 208\/240V–24V for PY3GNA030040AB","description":"\u003ch1\u003eOEM Carrier Control Transformer 40VA 208\/240V to 24V for Model PY3GNA030040AB\u003c\/h1\u003e\u003cp\u003eThis OEM Carrier control transformer (part #HT01BD209) is the factory-specified replacement for the \u003cstrong\u003eCarrier PY3GNA030040AB\u003c\/strong\u003e packaged unit. The transformer steps down high-voltage line power (208\/240V) to the 24V DC signal required by the control circuit — powering the thermostat, contactor coil, and every low-voltage control component in the system. When it fails, the entire control circuit goes dark: the thermostat becomes unresponsive, the unit will not start, and no fault codes will display on the board. A failed transformer is often misdiagnosed as a control board failure, making correct identification critical before ordering replacement parts.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 208\/240V primary input | 24V secondary output | 40VA power rating | 50\/60Hz | Factory-matched OEM tolerances for the Carrier PY3GNA030040AB\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound to exact VA and voltage tolerances. Undersized or off-spec generic units can cause erratic thermostat behavior, nuisance tripping of the low-voltage fuse, or premature contactor coil failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Always shut off all power to the unit at the disconnect before beginning. Tools needed: flathead and Phillips screwdrivers, multimeter (to verify 24V output after installation), wire nuts or spade connectors. Photograph all wiring before disconnecting terminals. Test for 24V output and check the low-voltage fuse before condemning the transformer.\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 as a direct OEM replacement for \u003cstrong\u003eCarrier model PY3GNA030040AB\u003c\/strong\u003e. Verify primary voltage on your unit's data plate (208V or 240V configurations) before ordering. Not sure this is the right part? Our HVAC parts specialists verify fitment before you order — contact us today and get your system back online fast.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640485499251,"sku":"CARRIE-PY3GNA030040AB-TRANSFORMER-HT01BD209","price":55.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640485532019,"sku":"CARRIE-PY3GNA030040AB-TRANSFORMER-HT01BD209-GEN","price":48.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01BD209_40810376-7a3a-45c2-9c20-8e9eaeb94d95.jpg?v=1775025669","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py3gna030040ab-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}