{"product_id":"tempstar-transformer-for-t9mpd075f12b1-40va-115v-to-24v-ships-today","title":"Tempstar Transformer for T9MPD075F12B1 — 40VA 115V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM control transformer (part number 1012722) is the 24-volt power source for your Tempstar T9MPD075F12B1 gas furnace. It steps line voltage down from 115V to 24V at a 40VA rating, supplying the low-voltage power that runs the thermostat, control board, gas valve, and ignition circuit. When a transformer fails, the furnace goes completely dead on the control side: no thermostat display, no blower, no ignition sequence, and often a blown low-voltage fuse on the control board. A buzzing or scorched-smelling transformer, or one reading 0V on its secondary terminals with line voltage present on the primary, indicates it has failed and needs replacement.\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 Direct 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\u003eDirect-fit replacement for the Tempstar T9MPD075F12B1 modulating gas furnace and the broader T9MPD \/ 9MPD furnace family built on the same ICP platform. The 115V-to-24V, 40VA configuration is shared across many Tempstar, Heil, Comfortmaker, and ICP furnaces — verify your existing transformer's voltage and VA rating 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 blower-compartment service panel to reach the control area.\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 — Disconnect the primary (115V) and secondary (24V) leads, then unbolt the transformer from its mounting bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, reconnect primary and secondary leads exactly per your photo, and confirm the leads are secure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24V across the secondary terminals and a normal call-for-heat sequence.\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 — no thermostat power and no ignition attempt\u003c\/li\u003e\n\u003cli\u003eRepeatedly blown 3A or 5A low-voltage fuse on the control board\u003c\/li\u003e\n\u003cli\u003e0V reading on the secondary with 115V present on the primary\u003c\/li\u003e\n\u003cli\u003eBuzzing, overheating, or a burnt-electrical smell from the transformer\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":63021681082739,"sku":"1012722-GEN","price":26.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048490549619,"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_c989ac38-94cf-4bc6-aad7-53ccfecd6d14.jpg?v=1782961440","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-transformer-for-t9mpd075f12b1-40va-115v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}