{"product_id":"tempstar-control-board-for-t4a424gkd100-comfortalert-diagnostic-ships-today","title":"Tempstar Control Board for T4A424GKD100 – ComfortAlert Diagnostic | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is the genuine OEM ComfortAlert control board (part #1177402) for the Tempstar T4A424GKD100 condensing unit. The ComfortAlert diagnostic module monitors compressor and electrical operation, detecting faults such as low\/high pressure trips, locked rotor, open circuit, low voltage, and welded contactor conditions, then communicates them through a flashing diagnostic LED. It protects the compressor by interpreting run behavior and flagging problems before they cause catastrophic failure. When this board fails, you may see no diagnostics, erratic compressor behavior, false fault codes, or a compressor that won't run despite a good call for cooling. Replacing it restores both system control and the built-in fault reporting technicians rely on.\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\u003eOEM Part Number\u003c\/td\u003e\n\u003ctd\u003e1177402\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eComfortAlert Diagnostic Control Board\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eControl Voltage\u003c\/td\u003e\n\u003ctd\u003e24 VAC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eCompressor Monitoring \u0026amp; Fault Diagnostics\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\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eDirect-fit OEM replacement for the Tempstar T4A424GKD100 condenser. Used across related ICP\/Heil\/Comfortmaker condensing units equipped with the ComfortAlert diagnostic platform. Verify the existing board is stamped 1177402 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 outdoor disconnect and verify zero voltage with a multimeter before handling the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e – Remove the condenser electrical access panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e – Photograph every low-voltage and sensor connection and note the board's mounting orientation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e – Unplug the connectors, release the standoff clips 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 its standoffs and reconnect every plug exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e – Restore power, call for cooling, and confirm normal operation and a steady (no-fault) diagnostic LED.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDiagnostic LED is dead, frozen, or flashing nonsensical codes.\u003c\/li\u003e\n\u003cli\u003eCompressor won't start despite a verified 24V call for cooling.\u003c\/li\u003e\n\u003cli\u003ePersistent false fault codes that clear when the board is bypassed.\u003c\/li\u003e\n\u003cli\u003eVisible scorching, swollen components, or burnt-smelling traces on the board.\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":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021806354803,"sku":"1177402-GEN","price":164.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048437137779,"sku":"1177402","price":214.44,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-furnace-1177402_59a912af-a8d7-4ac9-b89f-500ab2db0a46.jpg?v=1782959561","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-control-board-for-t4a424gkd100-comfortalert-diagnostic-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}