{"product_id":"tempstar-40va-transformer-for-t8mpv100j20a1-115v-to-24v-control-transformer-ships-today","title":"Tempstar 40VA Transformer for T8MPV100J20A1 — 115V to 24V Control Transformer | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is a genuine OEM 40VA control transformer (Part No. 1012722) for the Tempstar T8MPV100J20A1 furnace. It steps line voltage of 115V down to the 24V low-voltage control circuit that powers the thermostat, gas valve, igniter relay, and control board. Without a working transformer the entire 24V control system goes dead — the furnace will not respond to a thermostat call for heat. Common failure symptoms include a completely unresponsive furnace, a blank or dead thermostat, a humming or buzzing transformer, a blown low-voltage fuse, or a visibly scorched\/melted transformer body. Rated at 40VA, this transformer provides ample capacity for the control loads on this model.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\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)\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\u003eFit\u003c\/td\u003e\n\u003ctd\u003eOEM Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eEngineered as a direct OEM fit for the Tempstar T8MPV100J20A1 gas furnace. This 115V-to-24V 40VA transformer is also shared across many ICP-family furnaces sold under the Tempstar, Heil, Comfortmaker, and Arcoaire brands. Always confirm your existing transformer is a 115V primary \/ 24V secondary 40VA unit before ordering.\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety First\u003c\/strong\u003e — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter before touching any wiring.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the furnace control\/blower service panel to expose the control box.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph all primary and secondary wire connections before disconnecting anything.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Label and disconnect the 115V primary leads and 24V secondary leads, then unbolt the failed transformer from its mounting bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, reconnect the primary and secondary wiring exactly per your photo, and confirm tight connections.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, call for heat at the thermostat, and verify 24V on the secondary with your multimeter and normal furnace startup.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eFurnace is completely unresponsive to thermostat calls for heat.\u003c\/li\u003e\n\u003cli\u003eThermostat screen is blank or loses power.\u003c\/li\u003e\n\u003cli\u003eRepeatedly blown low-voltage (24V) fuse on the control board.\u003c\/li\u003e\n\u003cli\u003eTransformer is hot, buzzing, swollen, or shows burn marks.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\n\u003cp\u003eShips same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021692551539,"sku":"1012722-GEN","price":34.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048406008179,"sku":"1012722","price":44.2,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1012722_d9358e8c-437a-4df7-96e6-505d693bacc4.jpg?v=1782958352","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-t8mpv100j20a1-115v-to-24v-control-transformer-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}