Types of water shut-off valves

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Water shut-off valves interrupt the flow of water through pipes. Water shut-off valves are helpful when water must be turned off for maintenance or replacement of plumbing fixtures or to prevent frozen pipes. There are many types of water shut-off valves for different purposes and environments.


Water shut-off valves are used to turn water off for a variety of purposes. Each plumbing fixture in the home should have a separate shut-off valve to turn water off for upgrading fixtures, blockages, maintenance and to stop leaking and prevent damage to walls and floors until the fixture can be replaced. A water shut-off valve is also used to turn water off to exterior plumbing fixtures during winter to prevent frozen lines, which may burst pipes.


A lever, wheel or ball valve is a shut-off valve with a straight handle that is attached to a ball with an open centre. When the handle is turned to stop the flow of water, the solid sides of the ball prevent water from flowing through the pipe. Compression valves work by turning a knob that moves a solid shaft up and down in the valve. Automatic shut-off valves automatically turn water on and off based on the pressure on each side of the valve. These are often used in conjunction with reverse osmosis and other pressure tank water supplies.


Water shut-off valves are available in a wide variety of finishes and styles. They may be made from copper, brass, stainless steel or plastic. Shut-off valves are available with decorative finishes and attractive handles or knobs. Utility-purpose water shut-off valves are less expensive and lack the decorative finishes and handles. Quick-connect water shut-off valves are installed without solder, using compression fittings that make them easy for anyone to install.


There are many sizes of plumbing lines and water shut-off valves for each size. Main water supply pipes coming into the house have a larger diameter than water pipes for household plumbing. Appliances, such as refrigerators, have even smaller water lines that require small water shut-off valves to turn water off when servicing the appliance.


When installing or replacing a water shut-off valve, consider the type of valve appropriate for the location. Choose food-rated valves for sinks, refrigerators and other appliances that supply drinking water. Select a water shut-off valve that is of the same material as the connecting pipes. Hot water valves require a valve that can withstand high heat, while exterior valves require the ability to withstand temperature extremes.