{"product_id":"tempstar-defrost-control-board-for-t4h548gkd200-oem-heat-pump-board-ships-today","title":"Tempstar Defrost Control Board for T4H548GKD200 — OEM Heat Pump Board | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM defrost control board (part #1173636) is the brain of the defrost cycle on your Tempstar T4H548GKD200 heat pump. It monitors coil temperature and run time, then initiates and terminates defrost to keep the outdoor coil clear of frost during heating operation. It also coordinates the reversing valve, auxiliary heat, and fan timing. When this board fails, the unit may ice over in heating mode, fail to switch into defrost, run defrost too often, or lose heat-pump operation entirely.\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\u003eControl Voltage\u003c\/td\u003e\n\u003ctd\u003e24V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eHeat Pump Defrost Timing \u0026amp; Sequencing\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 fit for the Tempstar T4H548GKD200 heat pump. Commonly shared across ICP-family (Heil, Comfortmaker, Tempstar) heat pumps that specify defrost board #1173636. Confirm the 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, then verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the outdoor unit's electrical service panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every wire and the defrost timing\/pin-select jumper positions before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug the harness connectors and unscrew the old board from its standoffs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new board, set the defrost timing jumper to match the original, and reconnect each connector per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, run a heating call, and confirm normal operation and a proper 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 up heavily and never goes into defrost.\u003c\/li\u003e\n\u003cli\u003eUnit gets stuck in defrost or defrosts far too frequently.\u003c\/li\u003e\n\u003cli\u003eNo heat-pump heating despite the compressor running.\u003c\/li\u003e\n\u003cli\u003eErratic reversing-valve or auxiliary-heat behavior.\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":63021782040947,"sku":"1173636-GEN","price":129.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048446804339,"sku":"1173636","price":168.94,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_15ebc84e-aaf3-4617-b442-ec1228e3c682.jpg?v=1782959910","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h548gkd200-oem-heat-pump-board-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}