Most people have seen and used a shut-off valve in their home, particularly around plumbing fixtures, the water heater and sometimes even around the washer or the dishwasher. There are several different types of these valves, but their purpose is to either open up to allow flow through the pipe or to be turned down to shut off the flow of the media through the system.
There are many different designs in shut off valves. Most are made of brass or plastic, but it is also possible to have stainless steel types of valves that are used in sanitary processes or when corrosion resistance and durability is a factor for the system.
The interior configuration of the valve is not evident from the exterior of the valve, but there are several options to consider including ball and gate valves.
Gate shut off valves are common around the home. They have a round wheel-like handle that is turned clockwise to close and counterclockwise to open. The turning of the handle causes a flat, solid “gate” to close off the valve body directly under the handle.
The most common problem with the gate valve is that corrosion or debris in the water or in the system can result in a poor seal of the gate, allowing for some liquid or gas to continue through even if the valve is in the closed position.
Most ball shut off valves use a flat lever type of handle that turns 90 degrees for open or closed. The lever at the top controls the position of a valve, which has a hole drilled through it to allow the media to flow from the inlet to the outlet port when opened.
When closed, there is no way for any liquid or gas to get through, and it provides a secure seal even if rarely used. Ball shut off designs are easy to glance at and know if the valve is open or closed, and also easy to operate with just the ¼ turn requirement.