Geo-Flo manufactures and supplies check valves for flow centers and pump systems. Check valves are used in geothermal and hydronic systems when there are two or more pumps arranged in parallel. For example, when there are two or more geothermal heat pumps in a building and each heat pump has a dedicated flow center or pump(s), each flow center should have a check valve to prevent the fluid from short-cylcing through the other heat pump instead of the ground loop. A second example is when there are two central variable speed pumps plumbed in parallel serving multiple water source heat pumps. Check valves in closed loop geothermal and hydronic systems should be installed on the discharge side of the pump.