{"product_id":"tempstar-defrost-control-board-for-t4h360gkd300-oem-ships-today","title":"Tempstar Defrost Control Board for T4H360GKD300 — OEM | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis is a genuine OEM defrost control board (part number 1173636) for the Tempstar T4H360GKD300 heat pump. The defrost board is the brain of the outdoor unit in heating mode: it monitors coil temperature and run time, energizes the reversing valve and auxiliary heat, and periodically reverses the system to melt frost off the outdoor coil. When the board fails, the heat pump can ice over solid, get stuck in a permanent defrost cycle, fail to energize the compressor or fan, or lose communication with the thermostat. Because it controls both the changeover and the defrost timing, a bad board often presents as intermittent, hard-to-diagnose heating faults.\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\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApplication\u003c\/td\u003e\n\u003ctd\u003eHeat pump defrost \/ changeover control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFit\u003c\/td\u003e\n\u003ctd\u003eOEM direct replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eBuilt as a direct-fit replacement for the Tempstar T4H360GKD300 and equivalent Heil, Comfortmaker, and ICP-platform heat pumps using the same OEM part number. Match the board's connector layout and part number to your original before installing, as defrost boards are model-specific.\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 verify zero voltage with a multimeter before servicing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the outdoor electrical access panel to expose the control board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness plug, sensor lead, and terminal connection before unplugging anything.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug each connector, release the board standoffs or screws, and lift out the old board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Seat the new board on its standoffs and reconnect every harness and sensor exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, confirm the board powers up, and verify the unit heats and completes a normal defrost cycle.\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 never defrosts\u003c\/li\u003e\n\u003cli\u003eUnit stuck in continuous defrost or never enters defrost\u003c\/li\u003e\n\u003cli\u003eNo compressor or fan output despite a valid heat call\u003c\/li\u003e\n\u003cli\u003eBoard shows no power, blown components, or burnt connectors\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\u003cp\u003eShips same day for orders placed before 3 PM CST. 30-day returns on unused parts. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021790691699,"sku":"1173636-GEN","price":169.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048442839411,"sku":"1173636","price":219.7,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_0916dc68-2e97-4799-9cb2-f9725603d3d5.jpg?v=1782959772","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h360gkd300-oem-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}