What causes a backflow preventer to leak? What causes a backflow preventer to leak?
A backflow preventer can leak if there is collection of dirt within the valves. This will prevent the valves from closing fully, and there will be drops of water around that area. It can also result from broken valves, or faulty ones that have not been maintained for a while. This might be the case in hard-to-access areas, such as connections from the well to the house, or from the water supply system to the boiler. In addition, a backflow preventer may leak if there is a lot of pressure that cannot be handled by the receiving pipe. This means a lot of the water will be stuck at the valves.