{"product_id":"payne-pa3znb036000aa-transformer-h30291","title":"OEM Payne Transformer 40VA 120V-24V for PA3ZNB036000AA","description":"\u003ch1\u003eOEM Payne Control Circuit Transformer 40VA for Model PA3ZNB036000AA\u003c\/h1\u003e\u003cp\u003eThis is the factory OEM replacement transformer (part# \u003cstrong\u003eHT01BD209\u003c\/strong\u003e) for the \u003cstrong\u003ePayne PA3ZNB036000AA\u003c\/strong\u003e split-system air conditioner. The transformer steps down 120V line voltage to the 24V AC signal that powers your thermostat, control board, contactor coil, and all low-voltage safety circuits. When this component fails, the entire control circuit goes dead — your thermostat goes blank, the system won't respond to any commands, and no fault codes are generated because the board itself has no power.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rated | 120V primary \/ 24V secondary | Class 2 transformer | Replaces OEM part number HT01BD209 | Factory-matched output tolerance\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e OEM transformers are wound and rated to exact factory specifications, ensuring stable 24V output under full load. Generic units frequently under-deliver voltage under load, causing erratic thermostat behavior, nuisance lockouts, and premature contactor failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Disconnect power at the breaker and verify voltage is absent before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter. Photograph all low-voltage wiring connections before disconnecting. Secondary terminals are color-coded for straightforward reinstallation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty against defects in materials and workmanship. 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 and verified for the Payne \u003cstrong\u003ePA3ZNB036000AA\u003c\/strong\u003e 3-ton split-system air conditioner. Confirm your existing transformer's VA rating and primary\/secondary voltages on the unit data plate or wiring diagram before ordering. Our parts specialists are available to verify fitment — order with confidence and get back to comfort fast.\u003c\/p\u003e","brand":"Payne","offers":[{"title":"OEM","offer_id":62908880290163,"sku":"PAYNE-PA3ZNB036000AA-TRANSFORMER-HT01BD209","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62908880322931,"sku":"PAYNE-PA3ZNB036000AA-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_8fb1ed2c-812d-4b22-8617-e5c421e812d1.jpg?v=1780718875","url":"https:\/\/nationalhvacparts.com\/products\/payne-pa3znb036000aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}