{"product_id":"tempstar-defrost-control-board-for-tch448aka1-heat-pump-ships-today","title":"Tempstar Defrost Control Board for TCH448AKA1 — Heat Pump | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM defrost control board (Tempstar part number 1086070) is the brain of the defrost cycle on the TCH448AKA1 heat pump. In heating mode, frost builds on the outdoor coil; the defrost board monitors coil temperature and run time, then commands the unit into a defrost cycle — reversing the valve, stopping the outdoor fan, and energizing auxiliary heat as needed — until the coil clears. When this board fails, the heat pump can ice over solid, run an endless or non-existent defrost cycle, lose heating capacity, or fail to switch between heating and cooling. Because defrost logic is model-specific, installing the correct OEM board restores proper, factory-timed defrost operation.\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\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003e1086070\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 Defrost Cycle\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM\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 TCH448AKA1 heat pump and shared across ICP-family heat pumps (Tempstar, Heil, Comfortmaker, ICP) that call for OEM part 1086070. Confirm the printed board number and connector layout against your existing board before ordering.\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, then verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the outdoor unit's control\/service panel to reach the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every harness, sensor, and terminal connection before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug each connector, release the board's standoffs or screws, and lift it out.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new defrost board 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 normal heating operation, and verify the unit initiates and terminates a defrost cycle correctly.\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 clears\u003c\/li\u003e\n\u003cli\u003eUnit stuck in continuous defrost or never defrosts\u003c\/li\u003e\n\u003cli\u003eNo heating, or no switching between heat and cool\u003c\/li\u003e\n\u003cli\u003eVisible scorching, corrosion, or burnt traces on the board\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":63021654737267,"sku":"1086070-GEN","price":164.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048448475507,"sku":"1086070","price":214.44,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1086070_fb260b5e-39be-48f7-86fe-b7205189f49d.jpg?v=1782959978","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-tch448aka1-heat-pump-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}