This system could have had a water hammer problem if the valve was closed to quickly or the pump was started up too quickly. The LDi SurgeGuard (provided it has been correctly sized and installed) will prevent any water-hammer occurring. When the valve is closed too quickly, normally all the liquid would have to suddenly stop. The Surgeguard provides a space into wich the liquid can flow. As it flows into the space, it compresses a gas-filled bladder, so as the space fills, the bladder provides an increasing resistance. In this way, the liquid can be decelerated more slowly, preventing the formation of a shock wave. The same process happens when the pump is started up too quickly.