Replacing a Valve

Installing a Shutoff Valve

A plumbing system should have a main shutoff valve that controls water to the whole house and intermediate shutoff valves that control water for various areas of the house. There also should be shutoff valves on the incoming cold supply line for a water heater and stop valves (also called fixture shutoffs) that control water leading to individual faucets and appliances.

If an old shutoff valve -- usually a gate or globe type -- leaks at the packing nut, make sure it's all the way open or closed. If it still leaks, try tightening the packing nut with pliers or an adjustable wrench. (Don't crank down too hard, or you could crack the nut.) If it still leaks or if it fails to completely shut off water, repair or replace it.

Stop valves are often cheaply made and may fail to shut off water completely or may leak from the packing nut. Replace a faulty stop valve with a ball-type model, which costs a little more but is very reliable.

A globe valve inhibits water flow even if it is in good working order. Replacing it with a ball valve may increase water pressure.


An hour or two to repair or replace a shutoff valve

Groove-joint pliers, pipe wrenches, wire brush, flux brush, propane torch, fiber shield, adjustable wrench

Working with supply pipe

Shut off water upstream from the valve.

Repair parts or a new valve, pipe-thread tape, flux, solder

Installing a New Valve: Step 1

If possible open a nearby union and disassemble a few pipes to get to the existing valve.

Installing a New Valve: Step 2

The new valve will be about the same size as the old one, so you shouldn't have to change any pipe lengths. (Have on hand a selection of nipples.) Wrap all threaded pipe ends with several windings of pipe-thread tape and assemble the parts.

Installing a New Valve: Step 3

Tighten the pipes and fittings as you go using two 14-inch pipe wrenches. Finish by assembling and tightening a union. Test for leaks.

Installing a Gas Shutoff Valve: Step 1

A house shutoff is usually on the gas meter. To shut off gas to the entire house, turn the valve slowly a quarter-turn with a pipe wrench. To make sure no one turns the gas back on, padlock the valve.

Installing a Gas Shutoff Valve: Step 2

Open a window to vent any residual gas. Ignite no flames. Using two pipe wrenches to avoid straining any of the pipe joints, remove the cap or old valve. Apply gas-rated pipe-thread tape clockwise.

Installing a Gas Shutoff Valve: Step 3

Screw the valve onto the pipe. Gripping the gas pipe with a pipe wrench, use an adjustable wrench to tighten the valve in place. Turn the gas on at the house shutoff. Test your work using liquid soap or test fluid.

Comments (2)
cshurtleff2 wrote:

I am sorry to inform you that the photo above of using tephlon tape on ANY gas pipe voids the warranty on ALL of your automatic gas valves and can cause them to stick open.

12/8/2011 04:51:54 PM Report Abuse
user1605 wrote:

your site sucks

7/13/2010 03:10:50 PM Report Abuse
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