{"product_id":"tempstar-defrost-control-board-for-t4h342gkd100-oem-1173636-ships-today","title":"Tempstar Defrost Control Board for T4H342GKD100 — OEM 1173636 | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis genuine OEM defrost control board (part #1173636) is the brain of the Tempstar T4H342GKD100 heat pump's defrost cycle. It monitors the defrost thermostat and time interval, then commands the unit into and out of defrost to clear frost and ice from the outdoor coil during heating operation. The board switches the reversing valve, manages the outdoor fan, and energizes auxiliary heat at the right moments. When this board fails, the heat pump either ices over solid (never defrosting) or defrosts far too often, killing efficiency and comfort.\u003c\/p\u003e\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\u003e24 VAC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eDefrost timing \u0026amp; cycle control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eDirect-fit replacement for the Tempstar T4H342GKD100 heat pump and the closely related ICP-family heat pumps (Heil, Comfortmaker, Arcoaire) that share this control platform. Match the part number and connector layout to your existing board before ordering.\u003c\/p\u003e\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 condenser\/heat pump electrical access panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness and pin connection before unplugging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug all connectors and release the board from its standoffs or mounting screws.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Seat the new board, reconnect every harness per your photo, and verify any defrost-interval jumper\/pin matches the original setting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and run a heating cycle; initiate a forced defrost to confirm the reversing valve and fan respond.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eOutdoor coil ices over and never defrosts in heating mode.\u003c\/li\u003e\n\u003cli\u003eUnit defrosts constantly or at the wrong times.\u003c\/li\u003e\n\u003cli\u003eNo auxiliary\/emergency heat during defrost.\u003c\/li\u003e\n\u003cli\u003eReversing valve doesn't switch on a defrost call.\u003c\/li\u003e\n\u003c\/ul\u003e\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":63021793640819,"sku":"1173636-GEN","price":145.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048441987443,"sku":"1173636","price":188.5,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_b15b596e-6dad-493e-832a-f6c2d26372b8.jpg?v=1782959740","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h342gkd100-oem-1173636-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}