Why backflow preventer

Backsiphonage is caused when a negative or reduced pressure exists in the potable supply water system. There are several common causes of backsiphonage, including water main repairs or breaks that are lower than the service point, and lowered main pressure due to high water withdrawal rate, such as fire-fighting or water main flushing. Backsiphonage can also be caused by undersized supply piping causing high velocity in pipelines and a reduced supply pressure on the suction side of a booster pump.

A cross connection is defined by the Canadian Standards Association CSA as any actual or potential connection between a potable water system and any source of pollution or contamination, such as non-potable water, industrial fluid or gas. A cross-connection is any temporary or permanent piping connection between a potable water system and a heating or cooling system, irrigation system or an auxiliary water system.

Examples are by-pass lines, change over devices, or make-up water lines. In the plumbing and heating industry there are several very common types of cross-connections that must be protected with backflow preventers. Fresh water make-up lines are used in most boiler and chiller applications, which may contain boiler treatment chemicals or glycols. Make up water lines are also often used for industrial chemically-treated baths. Fire sprinkler systems will often incorporate a hookup connection for the fire truck pumper to boost the pressure and flow to the sprinkler system.

Irrigation pumping systems on farms will pump water from irrigation channels into the sprinkler system. Many are also connected to the potable water system for times when natural sources water levels are low.

There are also potentially dangerous cross-connections that occur in residential applications. These include outside hose bibs and lawn sprinkler systems. All of these different types of cross-connections do not pose the same levels of threat to the general public. So when using backflow preventers it is important to also know about different degrees of hazards that a given application poses. The degree of hazard is based on the type of fluid that could flow back into the potable piping system.

If the fluid is considered toxic, it could create a health hazard, causing sickness or death. If the fluid is non-toxic it may be considered more of a nuisance, which could cause the taste, colour or appearance of the water to be affected, but will not be hazardous to health. Based on the application and the toxicity of the fluid, the degree of hazard will be considered to be minor, moderate or severe.

Well, water that appears clean is not always clean. In fact, the law in most of the states mandates one to conduct backflow tests regularly. However, having the test is for your benefit. Your plumber can advise you accordingly before choosing one over another.

Do you need expert plumbers in Columbia, SC? Contact us today for all your plumbing needs. Save my name, email, and website in this browser for the next time I comment. This is the first plumber I liked. They understood my problem, gave me a reasonable quote for the work, and arranged to do the work within 2 hours. When they got busy with their current client, and couldn't make it, they arranged to show up early on Saturday morning they waived the "weekend fee".

The technician had the experience and equipment to clear my drain quickly. He even helped clean up the mess that came out of my drain. Well done PTP!! It was good, they come, they do the job and I've always been satisfied. They come in, take a look at it and fixed it, and they completed the job when they come and I don't have any problems with them anymore, they did a great work and I would refer him to anyone.

Price was very reasonable and they are punctual. Click Here to Verify Our Licenses. What Is a Backflow Prevention Device? Types of Backflow Preventers There are a variety of backflow prevention devices that you can use at home or in a commercial building. Air Gap The air gap is probably one of the most popular and effective backflow preventers.

Atmospheric Vacuum Breaker The atmospheric vacuum breaker is an elbow-shaped preventer with an internal valve that prevents the backflow of water. Dual Check Valves Dual check valves mostly apply in residential homes to deter backflow resulting from cross-connections. Water that comes into a building from main water supply should only flow in one direction into the building. However, sometimes water pressure changes can cause water to flow back into the main water supply this is called backflow.

This is why backflow preventer valves are required in all commercial buildings. A backflow preventer is a device designed to prevent water from flowing back into the clean water supply.

The valve does not allow water to backflow even if there are water pressure changes in the plumbing. Because of this, backflow preventer systems are required to be inspected and tested annually by plumbers who are certified to test these types of systems. There are a few different types of backflow preventer valves that are used in commercial buildings. The water you receive in your home is delivered by a main water supply line that is connected to the water pipes on your property. The sanitary water is distributed through your pipes in a single direction to each fixture in your kitchen and bathroom.

The movement of water in the pipes beneath the ground or behind your walls is caused by water pressure. However, it is not abnormal for the water pressure in the main water pipes to change due to issues such as a burst pipe or a broken fire hydrant. Unfortunately, a small decrease in water pressure can cause the potable water in your pipes to flow in a reverse direction.

Once the clean water flows in a backward direction, it can become contaminated by local sewage systems. When the water in a local main water supply pipe starts to flow backwards, this issue is referred to as a backflow in the plumbing system. A backflow preventer valve is designed to prevent the water in your main water supply lines from flowing in a reverse direction.

The valve will distribute the sanitary water from the main supply pipes to the water lines beneath your foundation. Double check valves are engineered to keep toxic chemicals out of the sanitary water in your pipes. It is equipped with two check valves that are designed to close to eliminate the negative consequences of a drastic change in water pressure. In addition, the second check valve can be utilized when the other valve is stuck open. The two check valves in a double check assembly device may be connected with ball valves for troubleshooting and confinement.

This type of backflow preventer valve can be integrated with test cocks that allow technicians to connect test equipment to confirm whether the double check valve is operating. Double check valves are usually utilized to prevent water contamination in fire, lawn, and boiler systems. Reduced pressure zones are similar to double check backflow prevention devices because they are equipped with two check valves.

However, reduced pressure zones feature a relief valve that is engineered to open and release contaminated water.