Backflow valves are used to prevent contamination of public water supplies. They are mandatory in some buildings. You can find backflow valves in a variety of types, including pressure vacuum check valves and Floating ball check valves. Choosing the correct backflow valve for your home is vital to protecting your family and your home.
Check valves
Check valves are an important part of stormwater control systems. They allow for backflow prevention by controlling water velocity and differential pressure. Cracking pressure is the minimum amount of pressure required to open a check valve. The lower the cracking pressure, the more protection a community has from backflow flooding.
There are several types of check valves. Most are designed to prevent backflow of water through submersible sewage pumps and lift stations. Some are prone to corrosion and jamming. They can also become clogged with debris. Swing check valves and flap check valves are susceptible to problems due to corrosive fluids, abrasive materials, or suspended solids.
Floating ball check valves
Ball check valves are a great solution for preventing backflow of stormwater. They have a relatively low compression set and do not require any maintenance. They are available in different sizes, depending on the type of application. Generally, they are rated for a 5 to 7-year life span.
Ball check valves are self-cleaning, rotating devices that prevent debris from clogging the valve seat. They are easy to install and require minimal slope or clearance. Some models also feature polyurethane balls for use in abrasive media. They can be installed horizontally or vertically.
Pressure vacuum check valves
Pressure vacuum check valves for stormwater backfilling are an important tool in preventing the backflow of stormwater. These valves are designed to prevent backflow by using pressure differential and flow velocity to open and close them. A cracking pressure is the minimum pressure needed to open a check valve.
This type of valve is installed at the meter for residential homes. These valves do not have shutoff valves and are not tested in-line. Another type of pressure vacuum check valve for stormwater backflow is the Reduced Pressure Zone principle, which has a relief valve positioned between two check valves. RPZ valves are used in irrigation systems, hospitals, manufacturing facilities, and schools.
Reduced pressure zones
Reduced pressure zones on stormwater backflow preventers are designed to prevent polluted water from entering the potable water system. This type of backflow valve uses two independently operating spring-loaded check valves and a differential pressure relief valve. It also features four independent test cocks.
The reduced pressure zone (RPZ) in a stormwater backflow valve is a special safety feature that lets the user know whether the valve is functioning properly. RPZ backflow preventers are made up of two independent check valves, each with a relief valve that stormwater backflow valve opens to the atmosphere in case either fails. When the valve is working correctly, there should be no water coming from the relief valve, but if it does, maintenance is necessary.