{"product_id":"tempstar-40va-transformer-for-tne050b12g1-115v-to-24v-ships-today","title":"Tempstar 40VA Transformer for TNE050B12G1 — 115V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThe Tempstar 1012722 is a genuine OEM control transformer that steps 115V line voltage down to 24V at 40VA for the TNE050B12G1 furnace. This 24V output powers the control board, thermostat, gas valve, and relays — essentially the entire low-voltage control circuit. When the transformer fails, the furnace loses all control power: the thermostat goes blank or unresponsive, the control board shows no activity, and the unit will not start a heat or fan cycle. Transformers commonly fail from a low-voltage short (a pinched 24V wire or shorted gas valve), repeated overloading, or simple age-related winding breakdown. A blown transformer often gives off a burnt smell and may show a melted or discolored housing. Replacing it with the correct 40VA OEM unit restores stable control power and full system operation.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpec\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e1012722\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eControl transformer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar (ICP \/ Heil \/ Comfortmaker compatible)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Voltage\u003c\/td\u003e\n\u003ctd\u003e115V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Voltage\u003c\/td\u003e\n\u003ctd\u003e24V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRating\u003c\/td\u003e\n\u003ctd\u003e40VA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM direct replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eThis transformer is a direct OEM fit for the Tempstar TNE050B12G1 furnace and is used across many ICP-built Tempstar, Heil, and Comfortmaker units requiring 115V-to-24V 40VA control power. Verify your primary input is 115V and the VA rating matches before installing.\u003c\/p\u003e\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety First\u003c\/strong\u003e — Disconnect power at the switch and breaker, then verify zero voltage at the primary leads with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the furnace control\/electrical service panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph all primary (line) and secondary (24V) wire connections before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the primary and secondary leads, then unbolt the old transformer from its mounting bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new 40VA transformer, reconnect 115V primary and 24V secondary leads exactly per your photo, and confirm no shorts to chassis.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and verify 24V output at the secondary and that the thermostat and control board power up.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eBlank or dead thermostat and no control board activity\u003c\/li\u003e\n\u003cli\u003eFurnace will not start any heat or fan cycle\u003c\/li\u003e\n\u003cli\u003eBurnt smell or melted\/discolored transformer housing\u003c\/li\u003e\n\u003cli\u003eNo 24V reading at the secondary terminals\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\u003cp\u003eShips same day on orders placed before 3 PM CST. 30-day hassle-free returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021637599603,"sku":"1012722-GEN","price":26.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048412922227,"sku":"1012722","price":35.04,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1012722_8b63a0f5-f5d4-47b3-bfe4-53f2bf6aa879.jpg?v=1782958606","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-tne050b12g1-115v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}