Browse reversing valves at Stockpile Express and find an essential component for your heat pump. Reversing valves control the direction of the flow of refrigerant within the pump, thus changing the cycle from heating to cooling, or from cooling to heating. Find standard reversing valves as well as 4-way reversing valves for efficient defrosting of air-to-air and air-to-water heat pumps in our selection. We offer products from First Co., Modine, Robertshaw, and other trusted manufacturers; find the parts you need for your heat pump and other HVAC essentials at Stockpile Express.