{"product_id":"icp-40va-control-transformer-for-rgs300hdaa0aaaa-120-24v-ships-today","title":"ICP 40VA Control Transformer for RGS300HDAA0AAAA — 120\/24V | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis OEM control transformer steps the 120V line voltage of the ICP\/Heil\/Tempstar RGS300HDAA0AAAA furnace down to the 24V needed by the control board, gas valve, thermostat, and relays. Rated at 40VA, it supplies the low-voltage control circuit that runs the entire safety and ignition sequence. A failed transformer is one of the most common no-heat causes: when it opens or shorts, the furnace gets no 24V control power and nothing energizes. \u003cem\u003eNote: this listing covers the 24V control circuit for this model — verify your exact OEM part number, as the associated relays (1183814, 1178205) carry the same 24V coil rating.\u003c\/em\u003e\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\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\u003eICP \/ Heil \/ Tempstar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Voltage\u003c\/td\u003e\n\u003ctd\u003e120V\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\u003e40VA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRelated Relays\u003c\/td\u003e\n\u003ctd\u003e1183814 (DPDT 24V), 1178205 (DPST 24V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFits Model\u003c\/td\u003e\n\u003ctd\u003eRGS300HDAA0AAAA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eFits the ICP\/Heil\/Tempstar RGS300HDAA0AAAA gas furnace and other RGS-series units using a 120\/24V 40VA control transformer. Confirm primary\/secondary voltage and VA rating against your existing transformer before installing.\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 switch and breaker, then 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 all primary and secondary lead connections before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the leads, remove the mounting screws, and take out the failed transformer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new transformer and reconnect primary and secondary leads per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and confirm 24V across the secondary and normal furnace operation.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eNo 24V control power — thermostat and board are dead\u003c\/li\u003e\n\u003cli\u003eFurnace will not start despite a valid heat call\u003c\/li\u003e\n\u003cli\u003eBlown low-voltage fuse that fails again immediately\u003c\/li\u003e\n\u003cli\u003eBurnt smell or visible scorching at the transformer\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\u003cp\u003eShips same day on orders placed 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":63027283034483,"sku":"1183814-GEN","price":34.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63047950532979,"sku":"1183814","price":44.2,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-transformer-control-1183814_f72d47ec-2fb4-4d31-be09-f671958bb082.jpg?v=1782882319","url":"https:\/\/nationalhvacparts.com\/products\/icp-40va-control-transformer-for-rgs300hdaa0aaaa-120-24v-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}