{"product_id":"icp-furnace-control-board-for-rgs121hfcb0aaa-oem-kit-1183618-ships-today","title":"ICP Furnace Control Board for RGS121HFCB0AAA – OEM Kit 1183618 | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis is the genuine OEM furnace control board kit (part number 1183618) for the ICP Tempstar Heil RGS121HFCB0AAA gas furnace. The integrated furnace control board is the brain of your heating system — it manages the ignition sequence, monitors safety limits and flame sensing, controls the inducer and blower motors, and coordinates the gas valve timing. When this board fails, the furnace may fail to ignite, short-cycle, lock out, or stop responding to thermostat calls entirely. Common failure symptoms include a furnace that hums but won't start, an LED fault code on the board, blown low-voltage fuses, or intermittent no-heat conditions that come and go with temperature. This kit ships complete and ready to install as a direct replacement.\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\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e1183618\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eIntegrated Furnace Control Board Kit\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\u003eFits Model\u003c\/td\u003e\n\u003ctd\u003eRGS121HFCB0AAA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM Direct Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eGas Furnace\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eThis control board kit is engineered specifically for the ICP Tempstar Heil RGS121HFCB0AAA furnace and related ICP-family equipment using OEM part 1183618. Always verify the part number printed on your existing board before ordering. ICP, Tempstar, Heil, and Comfortmaker share many components across these gas furnace platforms.\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 furnace switch and breaker, then verify zero voltage with a multimeter before touching the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e – Remove the furnace blower\/control compartment service panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e – Photograph every wire and connector position on the board before disconnecting anything.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e – Unplug each harness, release the board mounting standoffs or screws, and lift the old board out.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e – Seat the new board on the standoffs and reconnect every harness exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e – Restore power, call for heat, and verify the full ignition sequence and blower operation.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eFurnace will not respond to the thermostat or fails to ignite\u003c\/li\u003e\n\u003cli\u003eVisible burn marks, corrosion, or a blinking fault LED on the board\u003c\/li\u003e\n\u003cli\u003eRepeated blown 3-amp low-voltage fuses\u003c\/li\u003e\n\u003cli\u003eIntermittent no-heat or short-cycling that resists other fixes\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\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":63027525157235,"sku":"1183618","price":246.94,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":63047523893619,"sku":"1183618-GEN","price":189.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-furnace-1183618_9ed849a0-8ac6-4f5c-ba1d-2c8a78985ab3.jpg?v=1782888121","url":"https:\/\/nationalhvacparts.com\/products\/icp-furnace-control-board-for-rgs121hfcb0aaa-oem-kit-1183618-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}