{"product_id":"carrier-py3ppa030040aa-transformer-h30291","title":"OEM Carrier 40VA Control Transformer 120V→24V — PY3PPA030040AA","description":"\u003ch1\u003eOEM Carrier 40VA Control Transformer for Model PY3PPA030040AA\u003c\/h1\u003e\u003cp\u003eThis OEM replacement control transformer (part number \u003cstrong\u003eHT01BD209\u003c\/strong\u003e) is the factory-specified unit for the \u003cstrong\u003eCarrier PY3PPA030040AA\u003c\/strong\u003e packaged heat pump system. The transformer steps down line voltage (120V) to the 24V signal voltage that powers your thermostat, control board, and all low-voltage switching circuits. When this part fails, the entire control circuit goes dead — the thermostat loses power, relays won't energize, and the system will not respond to any heating or cooling demand.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecs:\u003c\/strong\u003e 40VA rating | Primary: 120V | Secondary: 24V | Class 2 transformer | Factory-matched OEM tolerances for the PY3PPA030040AA platform\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e The OEM HT01BD209 is wound to exact Carrier VA and impedance specs. Generic transformers with loose tolerances can brown out under full relay load, causing erratic cycling and premature control board failure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall difficulty: 2\/5\u003c\/strong\u003e — Always shut off power at the breaker and disconnect panel before servicing. Tools needed: flathead and Phillips screwdrivers, wire stripper, multimeter (to verify 24V output after install). Label all low-voltage wires before disconnecting from the old transformer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1-year OEM factory warranty. In-stock and ships the same business day from our warehouse.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Designed for the Carrier \u003cstrong\u003ePY3PPA030040AA\u003c\/strong\u003e packaged heat pump unit. Always verify your existing transformer's VA rating and primary\/secondary voltages on the unit data plate before ordering to ensure a correct fit. Have questions about compatibility? Our HVAC parts specialists confirm fitment before you buy — reach out before placing your order.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640370876787,"sku":"CARRIE-PY3PPA030040AA-TRANSFORMER-HT01BD209","price":34.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640370909555,"sku":"CARRIE-PY3PPA030040AA-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_74696ba2-894e-48f7-8878-ed4778dbed28.jpg?v=1775016218","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py3ppa030040aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}