{"product_id":"tempstar-40va-transformer-for-t8mpt075f14a1-115v-to-24v-control-transformer-ships-today","title":"Tempstar 40VA Transformer for T8MPT075F14A1 — 115V to 24V Control Transformer | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM 40VA control transformer (part number 1012722) supplies the 24-volt control power for the Tempstar T8MPT075F14A1 gas furnace. It steps the 115V line down to a 24V secondary that runs the control board, gas valve, thermostat circuit, and inducer relay. Rated at 40VA, it has the headroom to carry the furnace's control loads plus a typical thermostat and accessory. When a transformer fails — usually from a shorted low-voltage wire or an overloaded control circuit — the furnace goes completely dead at the thermostat: no display, no call for heat, and no response from the control board even though 115V line power is present. A blown transformer is a frequent root cause behind an unresponsive furnace.\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 platform)\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\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\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eFurnace Control Circuit\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\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eBuilt for the Tempstar T8MPT075F14A1 furnace and the shared ICP \/ Heil \/ Comfortmaker control platform that uses a 40VA, 115V-to-24V transformer. Confirm the primary and secondary voltages against your existing transformer before installing.\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 and verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the control compartment service panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph the primary (line) and secondary (24V) wiring before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the leads, remove the transformer mounting screws, and lift out the failed unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, then reconnect the 115V primary and 24V secondary leads exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, confirm 24V across the secondary, and verify the thermostat and control board power up and call for heat.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eFurnace completely dead — no thermostat display or response\u003c\/li\u003e\n\u003cli\u003eNo measurable 24V on the secondary while 115V is present on the primary\u003c\/li\u003e\n\u003cli\u003eBurnt smell or visibly scorched transformer windings\u003c\/li\u003e\n\u003cli\u003eRepeated control-fuse blow after a low-voltage short\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":63021726794099,"sku":"1012722-GEN","price":27.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048405188979,"sku":"1012722","price":36.34,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1012722_9bce8d29-93ba-4537-9a1f-1815246add44.jpg?v=1782958319","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-t8mpt075f14a1-115v-to-24v-control-transformer-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}