{"product_id":"icp-step-down-transformer-for-x9mpt125l20b1-40va-115v-to-24v-ships-today","title":"ICP Step-Down Transformer for X9MPT125L20B1 — 40VA 115V to 24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is a genuine OEM 40VA control transformer (part number 1012722) for the ICP Tempstar Heil X9MPT125L20B1 gas furnace. The transformer steps line voltage down from 115V on the primary side to 24V on the secondary side, powering the low-voltage control circuit that drives the thermostat, gas valve, ignition control board, and relays. The 40VA rating supplies enough capacity to run these control loads together. When the transformer fails, the entire 24V control system loses power — the furnace will not respond to a thermostat call, the control board goes dark, and the unit is inoperative even with line voltage present.\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\u003eICP (Tempstar \/ Heil)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVA Rating\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\u003e115 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Voltage\u003c\/td\u003e\n\u003ctd\u003e24 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFit\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\u003eEngineered for the ICP Tempstar Heil X9MPT125L20B1 two-stage gas furnace. This 40VA 115\/24V transformer is also used across many ICP-family (Tempstar, Heil, Comfortmaker, Arcoaire) gas furnace platforms. Confirm your existing transformer is rated 40VA with a 115V primary and 24V secondary 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.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the furnace control\/blower compartment service 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 — Label and disconnect the primary (115V) and secondary (24V) leads, then unbolt the failed transformer from its bracket.\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.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24V across the secondary terminals and normal furnace startup.\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 with line voltage present\u003c\/li\u003e\n\u003cli\u003eFurnace completely unresponsive to a heat call\u003c\/li\u003e\n\u003cli\u003eRepeatedly blown low-voltage fuse on the control board\u003c\/li\u003e\n\u003cli\u003eBurnt smell or visible scorching on the transformer housing\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":"OEM","offer_id":63021459669363,"sku":"X9MPT125L20B1","price":37.7,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":63047719584115,"sku":"X9MPT125L20B1-GEN","price":29.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-X9MPT125L20B1.jpg?v=1782895945","url":"https:\/\/nationalhvacparts.com\/products\/icp-step-down-transformer-for-x9mpt125l20b1-40va-115v-to-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}