Water valves are used in residential and commercial plumbing systems to direct water flow, prevent backflow, control water pressure, and restrict flow of water. There are different valves depending on how and where they are used. Moreover, the valves are available in different materials like PVS, brass, and bronze, and each type has pros and cons.
This article will outline different types of water valves, their applications, pros, and cons.
Types Of Water Valve
Understanding the different types, locations, and functions of water valves is crucial because it will allow you to turn off the water during plumbing emergencies and prevent further water damage. Here are different types of water valves with their advantages and disadvantages.
Ball valves are designed with a hollow in the middle connected to a large lever handle that rotates up to 90 degrees. They are among the most common and reliable valves used in residential plumbing.
Ball valves are mostly used in main water shutoffs and branch line shutoffs because they do not easily leak or seize. The valves open and close easily with a ¼ turn of the lever. You must open the lever fully to get a full water flow or close it completely to seal the hole at the center and stop the water from flowing.
When the ball valve is open, the lever aligns with the pipes. When it is in closed position, the lever is perpendicular to the water pipe. The position of the lever handle tells whether the water is ON or OFF.
Ball valves stand out because they provide a tight seal compared to other types of water valves. However, it isn’t easy to control water flow because it has three water flows at zero, 45, and 90 degrees.
There are different types of ball valves, including 3-way ball valves, three-piece body, split body, and floating ball valves.
Advantages of ball valves
- They have a tight seal when properly closed
- They are versatile because they come in small and large sizes. Small sizes can be used in water pipes under the sink, while large sizes can be used to control water flow at large pipes that supply water to the whole building.
- They are easy to open and close
- They can withstand high water pressure without damage
- Ball valves are cheaper compared to other water valves used for the same purpose
Disadvantages of ball valves
- They do not offer precise flow control because they have positive stops
- The hollow at the center is prone to clogging when used in areas where the water has a lot of debris and dirt
Gate valves are designed with a wedge-shaped metal gate and a wheel-shaped knob. Twisting the knob can either raise the valve and turn it on or lower it to turn it off. They are majorly used in main water shutoffs. Gate valves are available in different types, including solid wedge, flexible wedge, and non-raising stem gate valves.
Gate valves are suitable for controlling water flow because they can open and close slowly. However, the valve nuts loosen up faster if the valve is used to control water flow frequently.
Moreover, the valve seizes and becomes unusable if they are never used because the internal metal corrodes over time. For long service, gate valves should be used to allow full water flow or stop water flow infrequently.
Another downside of gate water valves is that the lowering and raising of the valve can only be done manually, which is difficult and time-consuming.
Advantages of gate valves
- The gate opens fully to allow for full water flow
- It opens and closes slowly, which modifies water flow hence preventing or fixing water hammering that is harmful to the pipes
Disadvantages of gate valves
- Internal parts of the gate valve corrode easily
- Manual operation of the gate valves is tedious and leads to a slow operation which can be costly when handling a plumbing emergency.
A butterfly valve has a rotating disc resembling a butterfly, hence the butterfly valve. On the outside, it has a lever that is used to open and close. It uses a revolving mechanism to control the water flow. The water flows around the butterfly disc, which allows it to flow out when it opens and stops the flow when it closes.
There are different types of butterfly valves, including double offset, triple offset, wafer type, zero offsets, and flanged ends butterfly valves. The major advantage of butterfly valves is that they are lightweight, take minimal space, and are easy to open and close. On the downside, the gasket inside the butterfly valve requires regular maintenance.
Advantages of butterfly valves
- Lightweight and compact
- Easy to manually operate
- Cheaper than ball valves
Disadvantages of butterfly valves
- The gasket inside requires frequent maintenance and replacement
- Slows down water flow
- Not durable
Globe valves have a bulge on their body and hence the name globe. There are different types of glove valves, including Z types, Y types, and angled types. They are used to modulate and limit the water flow of plumbing systems. The interior of the globe valve features a stopper which is adjusted using a twist knob.
When the knob is turned, the stopper is raised or lowered to allow or restrict the water flow. The knob can also be partially opened to reduce water pressure and the amount of water coming out.
Glove valves stand out for their ability to regulate water flow, and as a result, they are used for outdoor faucets, kitchen faucets, and other faucets with the same function.
Advantages of globe valves
- They are suitable for plumbing applications that require regular adjustment because they are designed with throttling abilities.
- They are easy to maintain
Disadvantages of globe valves
- They cause the water pressure drop
- They cause water flow restriction even when the valve is fully open
Pressure relief valve
Pressure relief valves are designed to ensure that water pressure remains at the desired levels to prevent the pipes and other plumbing tools from bursting. The system features a spring and a diaphragm valve that is set depending on the water pressure of the specific plumbing system.
Pressure relief valves do not open or close to allow or restrict water flow, instead, they regulate the flow to maintain the desired water pressure. They are mostly installed in homes supplied with high-pressure water, which might damage the plumbing system and appliances.
Pressure relief valves are also known as pressure-reducing valves, safety relief valves, vacuum relief valves, and pressure balance valves.
Advantages of pressure relief valves
- Reliable if properly fitted
- They can be used to regulate water pressure in other applications like water tanks, firefighting equipment, and water towers.
Disadvantages of pressure relief valves
- It may increase water pressure if there is back pressure in the pipeline
A check valve is designed to allow water to flow in one direction only. They are used in the plumbing system to prevent backflow, which can lead to cross-contamination. Most check valves do not need manual operation; therefore, they do not have operational handles or levers.
The valve has a hinged disk pushed open by the pressure of the incoming water. The same disc closes after the water passes through to stop it from flowing in the opposite direction. Check valves are also used in outdoor faucets and sprinkler systems.
Advantages of check valves
- Prevents backflow
- Fast acting to prevent possible contamination
Disadvantages of check valves
- The hinged disk wears down faster because of the opening and closing element
Needle valves, also referred to as saddle valves, connect water tubes to plumbing appliances like refrigerators or water filters. They a designed to clamp on the piping system and stick out a needle with a hole at the center to control the water flow. A water tube is then connected to the valve to supply the appliance.
Needle valves regulate the amount of water entering the appliance to prevent damage. Although the water inlet and the needle are very tiny, needle valves can withstand high water pressure without damage.
However, the building construction code no longer encourages the use of needle valves. The new codes require that water supply connections to plumbing appliances be made with fixture shutoff valves.
Advantages of needle valves
- Controls the water flow rate with precision
- They prevent water wastage because they can adapt to all low-flow applications
Disadvantages of needle valves
- It can only be used for low-flow applications
- It is difficult to tell whether the valve is open by looking at the valve
Factors To Consider When Selecting A Water Valve
Water valves are essential in the home plumbing system. However, selecting the right one can be a daunting task because there are many options with varying features and functions to choose from. Here are important factors to consider to help you choose the right water valve.
Water valves perform different functions, including regulating water flow, pressure relief, shutoff flow, and preventing backflow. To purchase the right water valve, you must understand its function and ensure that it matches your needs. For instance, a check valve is the guy for you if you want to prevent backflow.
Moreover, it would help if you determined whether you need a valve that turns off the water fully or partially. For instance, ball valves can only fully turn the water on and off. On the other hand, globe valves are designed for throttling, therefore, suitable for piping systems that require regular adjustment for variable water flow.
Size of the valve
The right size of the valve depends on the water pressure. When the size of the valve and the water pressure is matched, it produces effective performance. Under sizing leads to leakage, but you should also be careful to avoid buying an oversized one.
The material used to make the valves
The valve material you choose depends on whether the pipes carry hot or cold water. Identifying the water temperature helps you to choose a water valve made with a material that can withstand extreme temperatures. Purchasing compatible materials ensure effectiveness and long-term service.
Water and shower valves require regular maintenance and some replacement after some time. Check the manual for maintenance guides and stick by it to ensure stability and long service.
Note that some valves require more regular maintenance than others. Therefore, you can choose to purchase the types that serve you long before the need for maintenance or replacement.
Location of the valve
When purchasing valves for plumbing fixtures, it is crucial to determine if the fixture requires angled or straight valves. The location of the valve determines this.