{"product_id":"carrier-py3gnaa36090aa-transformer-h30291","title":"OEM Carrier 40VA Control Transformer for PY3GNAA36090AA Furnace","description":"\u003cdiv class=\"product-content\"\u003e\n\u003ch1\u003eOEM Carrier 40VA Control Transformer for PY3GNAA36090AA Furnace\u003c\/h1\u003e\n\u003cp\u003eThe control transformer steps your home's 120\/240-volt line voltage down to the 24-volt low-voltage signal that powers the thermostat, gas valve, control board relays, and inducer circuit throughout your Carrier system. When it fails, nothing on the low-voltage side responds: the thermostat screen goes dark, the furnace won't fire, the blower stays silent, and the air conditioner won't engage even though the breaker is on. A failing transformer may also hum loudly, give off a burnt-varnish smell, or trip its internal protection intermittently — making the system work one moment and die the next.\n\nThis is a 40VA, 24-volt secondary control transformer with a primary tapped for 120\/208\/240 VAC, delivering roughly 1.67 amps — enough to drive the ignition control board, inducer relay, and gas valve simultaneously. OEM units use a correctly sized magnetic core and Class B insulation rated to absorb the inrush of the gas valve and contactor coils without overheating.\n\nTransformers look interchangeable, but an undersized aftermarket unit (often only 20-25VA) sags under load, dropping voltage below the 18V threshold the gas valve needs to stay open. That causes nuisance lockouts and short-cycling that are nearly impossible to diagnose. The OEM VA rating and tap configuration guarantee stable 24V under full system load.\n\nInstall difficulty: 2\/5. Tools needed: 1\/4\" and 5\/16\" nut driver, multimeter, wire strippers. Label every lead before disconnecting it. #1 safety warning: KILL THE BREAKER first — the primary side carries full line voltage that can shock or kill you even with the thermostat off.\n\nShips same business day from our stocked warehouse on orders placed before 3 PM CST. Backed by a 1-year OEM warranty and 30-day hassle-free returns on uninstalled parts.\u003c\/p\u003e\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThis part is compatible with Carrier model PY3GNAA36090AA. Always verify the part number against your unit's data plate before ordering.\u003c\/p\u003e\n\u003ch2\u003eWhy Choose OEM?\u003c\/h2\u003e\n\u003cp\u003eOEM parts are manufactured to the exact factory specifications for your unit. Generic aftermarket alternatives may fit physically but often use lower-rated components that reduce equipment life and void manufacturer warranties. When the cost difference between OEM and generic is $10-30, the OEM part is always the smarter investment on a system worth $5,000-$15,000.\u003c\/p\u003e\n\u003ch2\u003eShipping \u0026amp; Returns\u003c\/h2\u003e\n\u003cp\u003eSame-day shipping on orders before 3 PM CST. Standard delivery 2-5 business days, express options available at checkout. 30-day hassle-free returns on uninstalled parts — free return shipping included. 1-year OEM factory warranty coverage.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640453812595,"sku":"CARRIE-PY3GNAA36090AA-TRANSFORMER-HT01BD209","price":47.25,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640453845363,"sku":"CARRIE-PY3GNAA36090AA-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_152cd32c-1de8-429c-9957-1c56e17526a7.jpg?v=1782899545","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py3gnaa36090aa-transformer-h30291","provider":"National HVAC Parts","version":"1.0","type":"link"}