{"product_id":"icp-40va-transformer-for-sh7512b-120v-to-24v-ships-today","title":"ICP 40VA Transformer for SH7512B — 120V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is the OEM 40VA control transformer (part 1540352) for the ICP \/ Tempstar \/ Heil SH7512B. It steps 120V line voltage down to the 24V required to power the control board, thermostat, gas valve, and low-voltage relays. The transformer is the heart of the furnace's low-voltage circuit — when it fails, the entire 24V side goes dead, leaving a blank thermostat and a furnace that will not respond to a call for heat. The most common cause of failure is a shorted 24V control wire that overloads and burns out the secondary winding.\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\u003e1540352\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\u003eICP \/ Tempstar \/ Heil\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\u003e120 VAC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Voltage\u003c\/td\u003e\n\u003ctd\u003e24 VAC\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 for the ICP \/ Tempstar \/ Heil SH7512B and other furnaces in the same family that use a 120V-to-24V 40VA control transformer. Confirm your existing transformer's primary and secondary voltage and VA rating against the failed 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 service switch and breaker, then verify zero voltage at the transformer leads with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the furnace control \/ burner compartment panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph all primary and secondary wire connections before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the 120V primary and 24V secondary leads, then unbolt the transformer from its bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer and reconnect primary and secondary wiring exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24VAC across the secondary and a normal 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\u003eNo 24V control power — thermostat is blank or unresponsive.\u003c\/li\u003e\n\u003cli\u003eFurnace will not start despite a valid call for heat.\u003c\/li\u003e\n\u003cli\u003eMeasured secondary voltage is zero or well below 24VAC.\u003c\/li\u003e\n\u003cli\u003eVisible scorching, swelling, or a burnt smell at 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":"ICP","offers":[{"title":"Direct Replacement","offer_id":63021832503667,"sku":"1540352-GEN","price":26.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63047952040307,"sku":"1540352","price":35.04,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1540352_85ab132f-d1a0-4d52-8ed8-51dc12b3eb52.jpg?v=1782882466","url":"https:\/\/nationalhvacparts.com\/products\/icp-40va-transformer-for-sh7512b-120v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}