Pool valves perform a variety of tasks, depending on the nature of the pool. The simplest valves work to either let water flow into the pool, or stop it from flowing. More complicated valves divert water in different directions or manage multiple water streams for filtration or flow systems.
The most simple valves are known as ball or gate valves. They simply open or shut, sealing pipes off as needed. These can either work with automated systems, opening at a specific time to replenish pool water and then closing again, or with manual controls so that pool water levels can be adjusted by hand. These valves are also used in outflow systems. Shut, they keep the water inside the pool; open, they let water flow out or circulate through a purifier. The terms gate and ball refer to the water-tight seal these valves make.
Flow Control and Diverter Valves
Another common type of valve is the flow control valve, which manages the water pressure of the pool system. Water flowing in too quickly can damage pipes or filtration units, and does not have enough time to be properly cleaned. Water flowing too slowly will not fill the pool properly and can cause blockages. Flow control valves ensure that water is moving through at the proper pressure, usually by stopping water at various sections to build the pressure higher, then releasing the water--or closing partway so only a certain amount can make it through.
These valves are helped by diverter valves. Diverters separate the water stream and send it to different spot around the pool, allowing the water to branch through multiple pipe systems. This is useful for filling the pool at multiple spots at once, and necessary for jet systems. These valves can also shut down access to certain parts of the pool system when they do not need to be used.
Multiport valves are a specialized type of valve that are used with pool filters. Essentially, these valves allow water to flow through different sections of the filter as needed, and allow purification chemicals to enter the water in specially built compartments. They are not used for any other pool applications, and are often considered part of the filtration system.
Many valves required some type of care. Lubrication needs to be applied to some valves at intervals, to ensure they are moving smoothly and can still form watertight seals in the pipes. Some newer types of pipes are designed to function without the need for regular lubrication, using advanced and especially durable plastics that resist wear and tear.