{"product_id":"tempstar-defrost-control-board-for-t4h424gkc200-24v-heat-pump-ships-today","title":"Tempstar Defrost Control Board for T4H424GKC200 — 24V Heat Pump | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is the genuine OEM defrost control board (part #1173636) for the Tempstar T4H424GKC200 heat pump. The defrost board is the brain of the outdoor unit's heating cycle: it monitors the defrost sensor and outdoor coil temperature, runs the defrost timing logic, energizes the reversing valve, controls the contactor and condenser fan, and triggers auxiliary heat during a defrost event. When this board fails, the heat pump may ice over and never clear, blow cold air in heating mode, short-cycle, or stop responding to the thermostat entirely. Because it coordinates nearly every high- and low-voltage function outdoors, a faulty board produces a wide range of symptoms.\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\u003eOEM Part 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\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\u003eDesigned for the Tempstar T4H424GKC200 heat pump and shared across matching ICP-built outdoor units (Heil, Comfortmaker, Arcoaire) of the same series. Verify the board's part number and connector layout against 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 disconnect and breaker; verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the condenser control-panel cover.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness connector and wire location on the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug the connectors, release the board standoffs\/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 to its matching plug per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, run a heating call, and confirm proper defrost initiation and termination.\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\u003eHeat pump blows cold air in heating mode.\u003c\/li\u003e\n\u003cli\u003eReversing valve or contactor won't energize on a call.\u003c\/li\u003e\n\u003cli\u003eErratic short-cycling or no response from the outdoor unit.\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":63021787775347,"sku":"1173636-GEN","price":98.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048443494771,"sku":"1173636","price":127.4,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_453c3726-6b36-4d98-9fe8-16a6119f6ac4.jpg?v=1782959802","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h424gkc200-24v-heat-pump-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}