{"product_id":"tempstar-defrost-control-board-for-t4h430gkb100-heat-pump-ships-today","title":"Tempstar Defrost Control Board for T4H430GKB100 — Heat Pump | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis genuine OEM defrost control board is the direct replacement for the Tempstar T4H430GKB100 heat pump. The defrost board is the brain of the outdoor unit's heating operation — it monitors the coil temperature sensor and time intervals to decide when to run a defrost cycle, energize the reversing valve, and switch the condenser fan. A failed defrost board causes frost or ice buildup on the outdoor coil, a heat pump that won't switch into defrost, short cycling, or the auxiliary\/emergency heat running constantly. Replacing the board restores proper defrost timing and protects efficiency through cold-weather operation.\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\u003e1173636\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eDefrost Control Board\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eTempstar \/ ICP \/ Heil\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eDefrost timing, reversing valve \u0026amp; fan control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eHeat Pump Outdoor Unit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\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 as a direct-fit replacement for the Tempstar T4H430GKB100 heat pump. The same board services equivalent ICP, Heil, Comfortmaker, and Arcoaire heat pumps built on the matching defrost platform. Confirm the OEM part number printed on your existing board 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 disconnect and breaker; verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the condensing-unit control-box cover to expose the defrost board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every wire, plug, and the defrost-time pin jumper position before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug the harnesses, release the board standoffs\/screws, and lift the old board out.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new board, set the defrost-time jumper to match the original, and reconnect every plug per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, initiate a defrost cycle, and verify the reversing valve and fan respond correctly.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eOutdoor coil ices over and won't go into defrost.\u003c\/li\u003e\n\u003cli\u003eHeat pump short cycles or won't switch between heat and defrost.\u003c\/li\u003e\n\u003cli\u003eAuxiliary\/emergency heat runs constantly.\u003c\/li\u003e\n\u003cli\u003eNo response from the reversing valve or fan during a defrost call.\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":63021787349363,"sku":"1173636-GEN","price":154.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048443691379,"sku":"1173636","price":201.44,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_bf57c5ef-0b51-4c78-ab8e-2485a1875566.jpg?v=1782959811","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h430gkb100-heat-pump-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}