{"product_id":"tempstar-defrost-control-board-for-t4h436gkc100-heat-pump-timer-ships-today","title":"Tempstar Defrost Control Board for T4H436GKC100 — Heat Pump Timer | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is the genuine OEM defrost control board (part 1173636) for the Tempstar T4H436GKC100 heat pump. The defrost board is the brain of the outdoor unit's heating cycle — it monitors the defrost thermostat and timer, decides when frost has built up on the outdoor coil, and initiates a defrost cycle by reversing the valve, stopping the outdoor fan, and energizing auxiliary heat. It also coordinates the contactor and reversing valve coil. When this board fails, the heat pump may ice over completely, skip defrost, run defrost constantly, or fail to energize the compressor and fan.\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 (ICP \/ Heil)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eControl Voltage\u003c\/td\u003e\n\u003ctd\u003e24V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eHeat Pump Defrost Control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM\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 T4H436GKC100 heat pump. Because this is an ICP\/Heil shared-platform board, it also services equivalent Tempstar, ICP, Heil, and Comfortmaker heat pump units that use part 1173636. Match the board's connector layout and part number to your existing board 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 breaker and disconnect, then verify zero voltage at the control board with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the condensing unit service\/control panel to expose the defrost board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness plug and spade connector and label them before unplugging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug all connectors, release the board standoffs or mounting 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 each harness and wire per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, verify the board powers up, and confirm a normal heating call and forced\/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 ices over and never defrosts\u003c\/li\u003e\n\u003cli\u003eUnit gets stuck in a continuous defrost cycle\u003c\/li\u003e\n\u003cli\u003eCompressor or outdoor fan won't energize in heat mode\u003c\/li\u003e\n\u003cli\u003eNo 24V output to the reversing valve or auxiliary heat\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. National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021786268019,"sku":"1173636-GEN","price":134.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048444215667,"sku":"1173636","price":175.44,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_ec37f719-3307-4ca6-a4c7-51d7c1776650.jpg?v=1782959832","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h436gkc100-heat-pump-timer-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}