{"product_id":"tempstar-40va-transformer-for-t8dnl075f16a1-115v-to-24v-ships-today","title":"Tempstar 40VA Transformer for T8DNL075F16A1 — 115V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM 40VA control transformer (part number 1012722, TRANS 115\u0026gt;24 40VA X) supplies low-voltage power for the Tempstar T8DNL075F16A1 gas furnace. It steps 115V line voltage down to the 24V required by the control board, thermostat, gas valve, and ignition circuit. A failed transformer leaves the entire low-voltage control system dead — no thermostat response, no ignition sequence, and no blower call. Transformer failure is often caused by a wiring short or a shorted 24V accessory, so inspect downstream wiring before replacing.\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\u003eStep-Down Control Transformer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar (Heil \/ ICP family)\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\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\u003eDirect-fit OEM replacement for the Tempstar T8DNL075F16A1 gas furnace. Also fits comparable Heil, Comfortmaker, and ICP-family furnaces that use a 40VA 115V-to-24V control transformer. Confirm primary\/secondary voltages and VA rating against your existing unit 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. Verify zero voltage with a multimeter before proceeding.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the furnace control\/electrical access panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph the primary (line) and secondary (24V) wiring connections before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the primary and secondary leads, remove the transformer mounting screws, and take out the old transformer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer, reconnect the 115V primary and 24V secondary leads exactly per your photo, and verify no leads are pinched.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, measure 24V at the secondary, and confirm the thermostat and ignition sequence respond.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eNo 24V at the control board or thermostat terminals\u003c\/li\u003e\n\u003cli\u003eFurnace completely unresponsive to thermostat calls\u003c\/li\u003e\n\u003cli\u003eBurnt smell or visible scorching on the transformer\u003c\/li\u003e\n\u003cli\u003eRepeated blown low-voltage fuse after a confirmed short is cleared\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\n\u003cp\u003eShips same day on orders placed before 3 PM CST. 30-day returns on unused parts. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021779747187,"sku":"1012722-GEN","price":26.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048401944947,"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_58bfaf4e-6752-47ac-b1cc-834cb6c3637b.jpg?v=1782958217","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-40va-transformer-for-t8dnl075f16a1-115v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}