{"product_id":"tempstar-defrost-control-board-for-t4h348gka200-oem-1173636-ships-today","title":"Tempstar Defrost Control Board for T4H348GKA200 — OEM 1173636 | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThis is the genuine OEM defrost control board (part number 1173636) for the Tempstar T4H348GKA200 heat pump. The defrost board is the brain of the outdoor unit in heating mode. It monitors the defrost thermostat and the time\/temperature defrost cycle, energizes the reversing valve and compressor, and switches the unit into a defrost cycle to clear ice from the outdoor coil before returning to normal heating. A failed board is a frequent cause of an outdoor coil that ices over solid, a heat pump that never defrosts, no compressor or fan operation in heat mode, or erratic changeover behavior. Replacing the board with the factory part restores the correct defrost logic and component sequencing for this model.\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 family)\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 and compressor sequencing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eOEM direct replacement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eDirect-fit replacement for the Tempstar T4H348GKA200 heat pump. The 1173636 board is shared across a range of ICP-built Tempstar, Heil, and Comfortmaker heat pumps of this series. Match the part number and connector layout to your existing board before ordering, as board revisions vary by production date.\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 before touching the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e — Remove the condensing unit service panel to reach the control box.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e — Photograph every wire, terminal, and connector on the existing board before disconnecting anything.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e — Label and disconnect the harnesses, then unclip or unscrew the old board from its standoffs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e — Mount the new 1173636, then transfer each connection to the matching terminal per your photo, confirming the defrost-time pin\/jumper setting matches the original.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e — Restore power, initiate a heat call, and verify normal operation and a correct forced or timed 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 ices over and the unit never defrosts\u003c\/li\u003e\n\u003cli\u003eNo compressor or outdoor fan operation in heating mode\u003c\/li\u003e\n\u003cli\u003eErratic or stuck heat\/cool changeover\u003c\/li\u003e\n\u003cli\u003eVisible burn marks, corrosion, or scorched 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 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":63021793018227,"sku":"1173636-GEN","price":169.0,"currency_code":"USD","in_stock":true},{"title":"OEM","offer_id":63048442315123,"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_fadc2ed7-6119-4f33-8011-0598902f352c.jpg?v=1782959751","url":"https:\/\/nationalhvacparts.com\/products\/tempstar-defrost-control-board-for-t4h348gka200-oem-1173636-ships-today","provider":"National HVAC Parts","version":"1.0","type":"link"}