{"product_id":"tempstar-40va-transformer-for-t8mpv075f14a1-115v-to-24v-control-transformer-ships-today","title":"Tempstar 40VA Transformer for T8MPV075F14A1 — 115V to 24V Control Transformer | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis OEM 40VA control transformer (part number 1012722, \"TRANS 115\u0026gt;24 40VA X\") supplies the low-voltage control power for the Tempstar T8MPV075F14A1 gas furnace. It steps 115V line voltage down to 24V to run the thermostat, gas valve, control board relays, and other low-voltage components. Rated at 40VA, it provides the current needed to drive these loads simultaneously. When a transformer fails — usually from a shorted secondary, an overloaded control circuit, or simple age — the furnace loses all 24V control power: the thermostat goes dark and the system will not respond to a call for heat or cool.\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\u003eStep-Down Control 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\u003e40 VA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eDirect-fit replacement for the Tempstar T8MPV075F14A1 furnace. This 115V-to-24V 40VA transformer is a common ICP service part used across many Tempstar, Heil, and Comfortmaker furnaces and air handlers. Confirm your primary voltage and VA rating before ordering.\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 furnace switch and breaker. Verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the control\/blower service panel to reach the transformer.\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 leads, remove the mounting screws or bracket, and lift out the failed transformer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer and reconnect the primary and secondary leads exactly per your photo, matching wire colors and terminals.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24V at the secondary and normal thermostat\/furnace operation.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eThermostat screen is blank and the system is completely unresponsive.\u003c\/li\u003e\n\u003cli\u003eNo 24V measured across the transformer secondary.\u003c\/li\u003e\n\u003cli\u003eRepeated blown low-voltage fuse on the control board.\u003c\/li\u003e\n\u003cli\u003eBurnt smell or visible discoloration on the transformer housing.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\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":63021695631731,"sku":"1012722-GEN","price":29.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048405844339,"sku":"1012722","price":38.94,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1012722_65a84ee0-62a7-45e3-8cdc-b8214ae9dc50.jpg?v=1782958345","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-t8mpv075f14a1-115v-to-24v-control-transformer-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}