{"product_id":"icp-control-board-for-wpa3484000rkc1-defrost-circuit-board-ships-today-1","title":"ICP Control Board for WPA3484000RKC1 – Defrost Circuit Board | Ships Today","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\u003cp\u003eThis OEM circuit control board (OEM 1178001) is the electronic brain of the ICP \/ Heil \/ Tempstar WPA3484000RKC1 heat pump. It manages the defrost cycle, compressor and fan timing, reversing-valve sequencing, and safety lockouts, coordinating the low-voltage signals from the thermostat with the high-voltage switching of the contactor. When a control board fails, the unit can stop running entirely, get stuck in defrost, ice up in heating mode, short-cycle, or ignore thermostat calls altogether. Burnt traces, scorched relays, swollen components, or a board that no longer energizes the contactor are clear failure signs, often caused by power surges, moisture intrusion, or a shorted control component. Replacing the board with this OEM unit restores proper defrost logic and reliable heat-pump operation.\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\u003e1178001\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType\u003c\/td\u003e\n\u003ctd\u003eDefrost \/ Sequencing Control Board\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eICP \/ Heil \/ Tempstar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eDefrost, timing, and reversing-valve control\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\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cp\u003eDirect OEM fit for the ICP \/ Heil \/ Tempstar WPA3484000RKC1 heat pump condensing unit. Used across ICP-family heat pumps that rely on this defrost control board for compressor and reversing-valve sequencing.\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 breaker and the outdoor disconnect. Verify zero voltage with a multimeter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAccess\u003c\/strong\u003e – Remove the control-panel service cover to reach the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocument\u003c\/strong\u003e – Photograph every wire harness, plug, and terminal position on the board before disconnecting.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemove\u003c\/strong\u003e – Unplug each connector, release the board standoffs or screws, and lift out the failed board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall\u003c\/strong\u003e – Seat the new board on the standoffs and reconnect every harness and terminal exactly per your photo.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTest\u003c\/strong\u003e – Restore power and confirm the unit starts, runs, and completes a normal defrost cycle without faults.\u003c\/li\u003e\n\u003c\/ol\u003e\u003ch3\u003eSigns You Need a Replacement\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eUnit won't start or ignores thermostat calls\u003c\/li\u003e\n\u003cli\u003eStuck in defrost or icing up in heat mode\u003c\/li\u003e\n\u003cli\u003eShort-cycling or erratic compressor and fan operation\u003c\/li\u003e\n\u003cli\u003eVisible burnt traces, scorched relays, or swollen components\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 hassle-free returns. Backed by the National HVAC Parts fitment guarantee.\u003c\/p\u003e","brand":"ICP","offers":[{"title":"OEM","offer_id":63027227394419,"sku":"1178001","price":219.7,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":63047465992563,"sku":"1178001-GEN","price":169.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-furnace-1178001_0e1057a2-5fbc-4ad9-b795-5f36f9d85137.jpg?v=1782885432","url":"https:\/\/nationalhvacparts.com\/products\/icp-control-board-for-wpa3484000rkc1-defrost-circuit-board-ships-today-1","provider":"National HVAC Parts","version":"1.0","type":"link"}