When you turn the spoked wheel handle, it actuates a screw drive that moves a flat metal partition (gate), inside the valve, up and down. With the gate fully closed, the water is shut off. But you can adjust the flow to a limited extent by leaving the gate partially open.

Shutoff valves are required equipment on home plumbing systems. The plumbing code requires a main shutoff for the entire system, and individual fixtures like sinks, toilets, outdoor faucets and washing machines should each have their own. These prevent a flood if a leak occurs, and makes general repairs easier.

Shut off Valve12V

A plumbing system needs a main shutoff valve as well as valves for branch lines and fixtures. Here's a rundown of the various types.

From the outside, a globe valve looks like a gate valve except for one feature: The valve body underneath the handle bulges slightly outward. Inside, the mechanisms of the two are different.

The type of valve that controls sprinkler systems and hydronic heating systems features a solenoid controlled by an external control panel. Valves for hydronic systems are usually brass, while sprinkler valves are most often plastic. The inlet and outlet ports may be parallel or angled with respect to each other, and they’re usually the same size.

This type of valve functions like a globe valve. It has three components: The valve body, consisting of the inlet and outlet ports separated by a baffle; a solenoid that raises and lowers a plunger to stop water flow; and a bonnet that contains a rubber diaphragm. The diaphragm regulates pressure inside the valve by raising and lowering it via a screw control on the top of the bonnet.

Shut-offvalveDanfoss

A standard (full-port) ball valve consists of a ball with a single hole installed in a tight-fitting chamber. Using the handle on top of the valve, you can rotate the ball through 90 degrees. When the hole aligns with the pipe, water flows freely. When it’s perpendicular to the pipe, the flow stops. It’s a non-adjustable, all-or-nothing valve.

Like ball valves, gate valves are bidirectional, meaning water can flow through them in either direction. They can be made of brass or PVC with screw thread, glue or sweat connections. They’re used as frequently as ball valves for main water shutoffs.

Also known as a saddle valve, this small shutoff is intended for use with copper tubing feeding refrigerator ice cube makers and furnace dehumidifiers. The valve attaches to a pipe clamp you tighten around the supply pipe. As you do this, a needle pierces the pipe and feeds water to a one-quarter-inch outlet port.

shut-offvalvetypes

Also known as a stop valve or angle stop, this is the common under-sink valve that’s also used for toilets. Most are made of chrome, brass or plastic. As the name suggests, the inlet and outlet ports are usually at right angles to each other.

Some angle stops incorporate gate or globe valves. Most contemporary ones contain ball valves, and you rotate the handle through 90 degrees to shut off the water.

Shut-offValveSMC

Disclaimer: This Code of Ordinances and/or any other documents that appear on this site may not reflect the most current legislation adopted by the Municipality. American Legal Publishing provides these documents for informational purposes only. These documents should not be relied upon as the definitive authority for local legislation. Additionally, the formatting and pagination of the posted documents varies from the formatting and pagination of the official copy. The official printed copy of a Code of Ordinances should be consulted prior to any action being taken. For further information regarding the official version of any of this Code of Ordinances or other documents posted on this site, please contact the Municipality directly or contact American Legal Publishing toll-free at 800-445-5588.

Instead of lifting and lowering a gate, the handle operates a plunger that presses against a valve seat when the valve is closed. There’s also a baffle that separates the inlet path from the outlet, reducing water pressure on the outlet side. The mechanism allows for more accurate pressure control.

Ball vales are most commonly used as the main water shutoff valve in a house, but they have multiple other uses as well. They come in a range of sizes with diameters, from huge to the tiny quarter-inch valves used for drip irrigation systems. The 64-inch CIRCOR valve, controlling water flow from the Ras Azawr desalination plant to Riyadh in Saudi Arabia, is the world’s largest.

Shut off valvefunction

Gate valves are usually found near the water heater, where one with a blue handle controls the cold water inlet and one with a red handle controls the hot water outlet.

Shut off valveaircraft

Shut-offvalvesymbol

Besides stopping the water altogether, some adjustable valves reduce pressure on a network by regulating the flow to it. They’re especially handy outdoors, letting you regulate the distance water travels to the sprinklers.

Needle valves are super easy to use. Although you may find one at the building supply store, installing it won’t meet code in most places. That is because any small impact can make the valve leak.

If you find an existing needle valve on your refrigerator water line, it’s best to replace it with a different kind of valve. Failing that, try not to disturb it and it probably won’t leak.

Shut off valvehydraulic

We are no longer supporting IE (Internet Explorer) as we strive to provide site experiences for browsers that support new web standards and security practices.

After a long, unsuccessful search for the main shutoff valve in the house, we purchased a special tool that allowed us to turn off the water at the street. We finally found the main shutoff by accident. It was outside, under a shrub and partially buried in the ground!

Unlike a gate valve, a globe valve is unidirectional. It has clearly marked inlet and outlet ports and must be installed so that water passes through it in the right direction.

Shutoff valves must be easy to find and access. Case in point: My friend needed a new toilet, and because his toilet shutoff valve was old and rusted, it had to be replaced as well. However, the bathroom lacked a dedicated shutoff valve.

The ports are also usually different sizes. The inlet port is usually 1/2- or 3/4-in. in diameter, while the outlet can be 1/4- to 1/2-in.-dia. Angle stops may have sweat or threaded connections, but most have compression fittings. These allow you to connect them to straight lengths of pipe without glue or solder.