Learn how to fix common problems with kitchen and bathroom faucets.
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Remove the valve. If you can, remove the seat, using a valve-seat wrench. Replace with a new one (Image 1).
In many cases, seat replacement is not possible, so screw a reseating tool into the thread of the faucet body (Image 2). Be sure to insert the faucet reseater carefully so that you do not damage the thread for the valve (Image 3).
Slowly turn the handle of the reseating tool to grind until the surface is smooth. Replace the valve and reassemble the faucet (Image 4).
There are a number of different types of valves found in domestic pipe runs. They are used to control water movement around the house, isolating areas as required for maintenance, or as an emergency mechanism to stop water flow. The most important valve is the stop valve, which controls the main water supply into the home. It is important that you know where to locate the stop valve in case of emergency. Others include gate valves and the various types of non-return and isolating valves.
All homes should have one main stop valve that controls the flow of the main water supply into the home. On large systems, a number of stop valves may be used to isolate various areas of a supply or system. If installing a stop valve, be aware that it must be installed correctly in relation to the directional flow of the water. This is indicated by an arrow on the outer casing. Stop valves are normally installed in a pipe run with compression hardware. Typically, they have a handle with a traditional shape.
Used as shutoff valves for the smaller areas of a plumbing system, isolating valves come in a number of different designs and should be located throughout a plumbing system. For example, an isolating valve may be installed close to a faucet. If the faucet needs replacing, it is then only necessary to turn off the water supply to that faucet rather than shut down a larger part of the water system. Isolating valves normally have an arrow on their outer casing to show that they must be installed in the same direction as the directional flow of the water. They may have a handle, or be closed and opened using a screwdriver.
The valve is open when the orientation of the groove in the grub screw that opens the valve is in line with the pipe. A quarter turn is all that is required to close down the water supply. Many plastic valves are only suitable to hold water up to a certain temperature. This should be indicated on the side of the valve along with the directional arrow.
Plastic push-fit/threaded isolating valve with handle (Image 1); Compression fit isolating valve (Image 2); Vacuum breakers (Image 3); Temperature and pressure release valve (Image 4)
Similar to stop valves, gate valves are used to isolate areas. However, they should only be used in low-pressure pipe runs. Gate valves do not have a right or wrong way around in terms of installation in relation to the directional flow of water. They are identified easily by their wheel handles.
Drain valves are positioned on a pipe run as the point to attach a hose when an area of plumbing requires draining. Use a drain valve key to operate the valve.
Toilets are made with vacuum breakers integrated into their design. The vacuum breaker can also be added on, to help prevent air locks. Vacuum breakers are available in a few different designs. They are internally spring loaded, so that they can sense any pressure backing up.
Temperature and Pressure Release Valve
When pressure and temperature build up inside a water boiler, a temperature and pressure release valve releases water to remove some of the pressure. Water heaters can explode if they are not relieved of pressure build up. Check your boiler or water heater to be sure you have one installed.
Pressure Reduction Valve
Proximity to your municipality’s water source can affect the water pressure you receive. If you are close to the source, you may want to install a pressure reduction valve. Having high water pressure may be a benefit in the shower, but it will cost you more money every time you run your sink.
A benefit if installed on outdoor faucets, a stop-and-waste valve allows you to drain water after you turn off the water.
If you are connecting a dishwasher and the kitchen faucet to hot water piping, you may need a dual stop. They operate like compression stops that connect water pipes to supply tubes, but they have the benefit of offering two outlet ports.
Check valves or non-return valves allow water to flow only in one direction. They are used mainly on outside faucets and mixer faucets/valves and are usually built into the design. Their function is to prevent the back siphonage of water down a supply pipe, which would contaminate the water supply.
Excerpted from Do It Yourself Home Improvement
© Dorling Kindersley Limited 2009