{"product_id":"tempstar-defrost-control-board-for-t4h348gke200-heat-pump-ships-today","title":"Tempstar Defrost Control Board for T4H348GKE200 — Heat Pump | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis OEM defrost control board (part #1173636) is the brain of your Tempstar T4H348GKE200 heat pump's defrost cycle. In heating mode, frost builds on the outdoor coil; the board monitors coil temperature and elapsed run time, then commands a defrost cycle by reversing the valve, shutting off the outdoor fan, and energizing auxiliary heat so the coil clears without blowing cold air indoors. It also coordinates compressor timing and lockout protection. When this board fails, the heat pump may ice over completely, run defrost too often (or never), short-cycle, or refuse to switch between heating and cooling. Symptoms like a frozen outdoor unit in winter or a reversing valve that won't shift usually trace back to a failed defrost board.\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\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\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eDefrost timing, reversing valve \u0026amp; fan control, compressor timing\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\u003eEngineered for the Tempstar T4H348GKE200 heat pump and shared across matching ICP, Heil, and Comfortmaker heat-pump platforms that use this defrost board. Match the printed part number on 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 confirm zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the control\/electrical access panel on the outdoor unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every wire and connector position on the existing board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Unplug the harness connectors and unscrew or unclip the board from its standoffs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Seat the new board on the standoffs and reconnect each harness exactly as photographed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power and verify a normal heating call and, if conditions allow, a forced defrost cycle.\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 freezes solid and never defrosts in heating mode\u003c\/li\u003e\n\u003cli\u003eConstant or excessively frequent defrost cycling\u003c\/li\u003e\n\u003cli\u003eHeat pump won't switch between heating and cooling\u003c\/li\u003e\n\u003cli\u003eVisible burn marks, corrosion, or failed relays on the board\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eShipping \u0026amp; Returns\u003c\/h3\u003e\n\u003cp\u003eShips same day on orders placed before 3 PM CST. 30-day hassle-free returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"Tempstar","offers":[{"title":"Direct Replacement","offer_id":63021791215987,"sku":"1173636-GEN","price":154.95,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048442544499,"sku":"1173636","price":201.44,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-defrost-1173636_1e5d3e30-cb15-4f6b-ba1a-1557124b200d.jpg?v=1782959761","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h348gke200-heat-pump-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}