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How does a backflow preventer work?

Backflow prevention devices are devices that are mounted on a pipe that allow water to only flow in one direction. Consider it a one-way gate that permits water from the city’s public water supply to flow into your home’s pipes but prevents water from flowing back into the main water supply. A backflow preventer valve is a device that prevents water from flowing backward in your main water supply lines. The valve will transmit sanitary water from the main supply pipes to the underground water lines.

What is a backflow prevention system?

Backflow prevention systems are pipe-mounted devices that only allow water to flow in one way. Moreover, Consider it a one-way ate that enables water from the city’s public water system to flow through your home’s piping but prevents water from flowing backward into the main supply.

The key to preventing backflow is to have a backflow prevention device that is properly installed, maintained, and inspected as part of your culinary water system. If you have a culinary water connection that could be utilized to supply a sprinkler system, you’ll need backflow prevention.



Everest Plumbing Nov 26, 2020
How does a backflow preventer work
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Are you looking to keep your residential and commercial water supply safe for use?

Similarly, The risks to drinking water quality from Backflow prevention contamination incidents create a constant threat whether they are annoyance, health hazards, or serious public health risks.

Even though, plumbing codes mandate the protection of  potable water supplies against backflow at all cross connections.

Moreover, It would be best to invest in one at your home or office which ensures clean water.

Also, It is also necessary to know about plumbing tips to avoided such consequences.

What is a backflow prevention device?

The water flowing on your taps passes through various connections before reaching your home. Usually, the water flows from the water treatment area, into the main water line.  But the changes in pressure can make the water flow backward, which is known as backflow.

The pressure in the pipes can drop if the water within the structure overflows or when the pipes freeze. The pressure changes in pipes can cause water to seep back into the main supply line and can pollute the public drinking supply with contaminants like fertilizers, pesticides, human waste and harmful chemicals. When the pipe water is contaminated, it can flow to your house, leading to consumption of unsafe water.

A backflow preventer is a device plumber install it on your home’s water pipe to stop non-potable water from flowing back into the primary water supply. This device ensures that water from the public or private suppliers flows in one direction.

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How does backflow preventer work?

Usually, a backflow preventer is simplistic yet ingenious in its design equipped with a pair of one-way valves that allows the flow of water through one way and then closes when there is pressure coming back through. These valves have a spring device that is occupied by the pressure of the incoming water.

The way these devices work is simple. Therefore, when the pressure on the mains side is high, the springs are engaged and the valves open up to allow inflow. But, as soon as the pressure on the inlet side falls below the outlet, the springs release the valves which prevents the backward flow of water. Beside, the valves are installed in pairs as redundancies to ensure that leakage or failure of one can be controlled by the other,keeping the device functional and more reliant and effective in their operation.
In the same way, the valves have test cocks and shutoff valves that are used for maintenance and testing purposes. An inspector or examiner can check the pressure differential and valve action from the test cocks. Likewise, the use of shutoff valves is to cut off the supply and disconnect the backflow preventer device for maintenance and repairs.

Types and structure of backflow preventer

Based on their design and application, you can get a lot of different versions and types of backflow preventer devices. All of these are designed for specific applications and have different levels to work for varying pressure and volume requirements. Some of the common backflow preventers are

  • Double Check Valves system (DCVs)
  • Reduced Pressure Zone (RPZ), and 
  • Pressure Vacuum Breaker (PVB)

DCVs are respectively designed to protect water supplies from contamination. It consists of two independently operating spring-loaded check valves, an inlet (upstream) shutoff valve,  four test cocks, and an outlet (downstream) shutoff valve. A DCVs is effective against backpressure backflow and backsiphonage.

RPZ valves’ the most safest and reliable backflow preventer offer protection against backpressure and siphonage in order to protect the mains water supply and drinking network from contamination. It consists of two independent check valves and they work like a double check backflow preventer. However, they also have an intermediate relief valve that opens to the atmosphere if both check valves fail. A house or business or industries can use all the water it wants, but once the water has passed through the RPZ backflow preventer, it will not be allowed to be back into the water supply. 

PVB, specially made for lawn irrigation systems to your home that provides protection against backflow, or back siphoning. They are relatively the least expensive, simple in design and the easiest to install, maintain, and repair.

What should you do when something goes wrong?

Having backflow preventers is mandatory in Toronto. The law demands everyone to have backflow preventers for high and low hazard cross-connections. If not, you will be liable for fines. As backflows are likely to damage pipes due to the foreign materials flowing through the pipes, investing in a quality backflow preventer is a great way to avoid expensive repairs and maintenance. because. If you don’t avoid the damage, the cost of repair might be overwhelmingly high. Also, you might have to stay for days without water during the repair period and you’re putting yourself at risk of health hazards. Installing a backflow prevention device and getting professionals to inspect it periodically means you don’t have to deal with the inconvenience and high repairing cost. 

Based on the plumbing rules, regulations and design of your system, you should choose a backflow preventer that is reliable and works best for your conditions. If the backflow preventer is already being placed in an existing home, as opposed to being installed in the initial construction, a plumbing permit from your municipality is needed. Consulting a professional and setting up a plumbing solution that works is the best for all.

Should you require the professional assistance to install, inspect and repair a backflow prevention device? The plumbers at Everest Plumbing can assess your issues and provide the best inspection and repair service you will need. We also offer the large selection of backflow prevention solutions for any application. Please feel free to contact us anytime.

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