{"product_id":"tempstar-defrost-control-board-for-t4h430gkd100-oem-1173636-ships-today","title":"Tempstar Defrost Control Board for T4H430GKD100 — OEM 1173636 | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is a genuine OEM defrost control board (part number 1173636) for the Tempstar T4H430GKD100 heat pump. The defrost board is the brain of the outdoor unit during heating: it monitors the defrost thermostat and timer, energizes the reversing valve, and cycles the unit into and out of defrost so frost doesn't build up on the outdoor coil. When this board fails, the heat pump may ice over solid in winter, never enter defrost, get stuck in defrost, fail to energize the compressor or fan, or lose proper reversing-valve control. Symptoms often include a heavily frosted outdoor coil, no heat, or erratic staging. This board is matched to the original specification for correct defrost timing and sequencing.\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\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\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\u003eFits Model\u003c\/td\u003e\n\u003ctd\u003eT4H430GKD100\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 OEM replacement for the Tempstar T4H430GKD100 heat pump and other ICP-family heat pumps (Heil, Comfortmaker, ICP) using the same defrost board. Confirm the exact board part number and connector layout before ordering, as defrost boards vary by chassis.\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.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the electrical panel covering the control board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every plug, terminal, and the defrost timer setting before unplugging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Disconnect the wire harnesses and unscrew\/unsnap the old board from its standoffs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new board, match the defrost timer jumper to the original, and reconnect each harness per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, run a heating call, and confirm normal staging and a forced or timed defrost cycle.\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 freezes over solid and never defrosts in heating mode.\u003c\/li\u003e\n\u003cli\u003eUnit gets stuck in defrost or cycles defrost too frequently.\u003c\/li\u003e\n\u003cli\u003eNo compressor or outdoor fan operation despite a heat call.\u003c\/li\u003e\n\u003cli\u003eReversing valve fails to switch, leaving the system stuck in heat or cool.\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":63021787021683,"sku":"1173636-GEN","price":169.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048443920755,"sku":"1173636","price":220.94,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_c2ce01ec-0140-4f9a-84d8-28af40e78457.jpg?v=1782959820","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h430gkd100-oem-1173636-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}