{"product_id":"payne-pa4gpxa42000aa-transformer-h30291","title":"OEM Payne Transformer 40VA 120V\/24V for PA4GPXA42000AA — HT01BD209","description":"\u003ch1\u003eOEM Payne 40VA Control Transformer for Model PA4GPXA42000AA — Part HT01BD209\u003c\/h1\u003e\u003cp\u003eThis OEM control transformer (part number \u003cstrong\u003eHT01BD209\u003c\/strong\u003e) is the factory-specified replacement for the \u003cstrong\u003ePayne PA4GPXA42000AA\u003c\/strong\u003e air conditioner. The transformer steps down 120V line voltage to 24V AC to power the entire low-voltage control circuit — including the thermostat, contactor coil, and control board. When the transformer fails, nothing in the system responds: the thermostat goes dark, the contactor won't energize, and the unit sits completely dead despite line power being present. A failed transformer is often the first suspect when a system stops responding with no obvious cause.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | 120V primary \/ 24V secondary | Single-phase | Designed to factory tolerance for the PA4GPXA42000AA control circuit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and insulated to exact VA and voltage specifications for this platform. Undersized or off-tolerance generic units can overheat, blow the secondary fuse repeatedly, or cause erratic low-voltage behavior across the control board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Shut off power at the disconnect and breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after install). Label or photograph all low-voltage wiring before disconnecting. Reconnect R, C, and secondary leads carefully to avoid reversing polarity.\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 stocked warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered as a direct OEM replacement for the Payne \u003cstrong\u003ePA4GPXA42000AA\u003c\/strong\u003e split-system air conditioner. Confirm your existing transformer is rated 40VA 120V\/24V by checking the data label on the transformer body before ordering. Not sure it fits? Our HVAC parts specialists verify fitment before you buy — \u003cstrong\u003eorder today and receive same-day shipping\u003c\/strong\u003e on all in-stock parts.\u003c\/p\u003e","brand":"Payne","offers":[{"title":"OEM","offer_id":62908860793203,"sku":"PAYNE-PA4GPXA42000AA-TRANSFORMER-HT01BD209","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62908860825971,"sku":"PAYNE-PA4GPXA42000AA-TRANSFORMER-HT01BD209-GEN","price":30.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-HT01BD209_6c4c6b3e-2e59-489e-bd83-18a2006f2aea.jpg?v=1780719028","url":"https:\/\/nationalhvacparts.com\/products\/payne-pa4gpxa42000aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}