{"product_id":"tempstar-defrost-control-board-for-t4h336gka100-heat-pump-ships-today","title":"Tempstar Defrost Control Board for T4H336GKA100 Heat Pump | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis genuine OEM defrost control board (part 1173636) manages the defrost cycle on the Tempstar T4H336GKA100 heat pump. In heating mode the outdoor coil accumulates frost; the defrost board uses time and temperature input (from the defrost thermostat\/sensor) to periodically reverse the system, energize the reversing valve, and melt the ice off the outdoor coil. It also controls the contactor and outdoor fan during defrost. A failed board can leave the outdoor coil iced over, cause the unit to never defrost, or trigger constant defrosting that kills efficiency.\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\u003eDirect OEM replacement for the Tempstar T4H336GKA100 heat pump. Defrost boards are model-specific in their timing logic and connector layout — confirm part number 1173636 against your unit 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 disconnect and breaker; verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the outdoor unit electrical panel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness connection and the defrost-time jumper\/pin setting before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug each connector and remove the board's mounting screws\/standoffs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new board, set the defrost timing pins to match the old board, and reconnect every harness per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and verify normal heating operation; initiate a forced defrost (per the board's test pins) to confirm the cycle works.\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 in heating mode\u003c\/li\u003e\n\u003cli\u003eUnit defrosts constantly or at the wrong intervals\u003c\/li\u003e\n\u003cli\u003eNo output to the reversing valve, contactor, or fan during defrost\u003c\/li\u003e\n\u003cli\u003eBoard shows scorched components or a blank\/dead diagnostic LED\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\u003cp\u003eShips same day on orders placed 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":63021794853235,"sku":"1173636-GEN","price":139.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048441135475,"sku":"1173636","price":180.7,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_3d26a480-146a-4498-bc66-c61b94d0bdf5.jpg?v=1782959720","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h336gka100-heat-pump-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}