{"product_id":"tempstar-defrost-control-board-for-t4h348gke100-oem-part-1173636-ships-today","title":"Tempstar Defrost Control Board for T4H348GKE100 — OEM Part 1173636 | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis is the genuine OEM defrost control board (part number 1173636) for the Tempstar T4H348GKE100 heat pump. The defrost board is the brain of the outdoor unit during heating mode. It monitors coil temperature and run time, then commands a defrost cycle to clear frost and ice from the outdoor coil so the system can keep pulling heat from the air. It also coordinates the reversing valve, condenser fan, and compressor timing, and provides anti-short-cycle protection on the 24V control circuit. When this board fails you will often see the unit ice over and never defrost, run defrost constantly, fail to switch between heating and cooling, or stop responding to the thermostat entirely.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\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 Outdoor Unit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFit\u003c\/td\u003e\n\u003ctd\u003eOEM Replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eEngineered as the factory replacement for the Tempstar T4H348GKE100 heat pump. Because Tempstar, Heil, Comfortmaker, and other ICP-built units share components, this board number is also used across related ICP outdoor models. Always confirm part number 1173636 against the board printed on your existing control before ordering.\u003c\/p\u003e\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety First\u003c\/strong\u003e — Disconnect power at the outdoor disconnect and breaker, then verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the control panel cover on the outdoor unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every wire and terminal on the existing board before disconnecting anything.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Label and disconnect the low-voltage and line-voltage leads, release the board standoffs or screws, and lift out the old board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new board on the same standoffs and reconnect each wire exactly as photographed, matching the defrost timer pin setting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, run a heating cycle, and confirm a normal defrost and reversing-valve changeover.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eOutdoor coil ices over and the unit never enters defrost.\u003c\/li\u003e\n\u003cli\u003eSystem runs defrost constantly or short-cycles between modes.\u003c\/li\u003e\n\u003cli\u003eHeat pump will not switch between heating and cooling.\u003c\/li\u003e\n\u003cli\u003eNo 24V output to the contactor or reversing valve.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\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":63021791281523,"sku":"1173636-GEN","price":119.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048442478963,"sku":"1173636","price":154.7,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_b47c355b-0533-4937-bb94-bc6a53e4a36e.jpg?v=1782959758","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h348gke100-oem-part-1173636-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}