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How does a backflow preventer work?

Backflow prevention devices are crucial for ensuring the safety of the public water supply by preventing water contamination through the backflow of water from a customer’s plumbing system. A backflow preventer valve is a specific type of device that prevents the reverse flow of water in the main water supply lines. This mechanical valve allows water to flow only in one direction, from the city’s public water supply to the customer’s plumbing system. In case of a drop in pressure in the main water supply, the valve closes to prevent the backflow of water into the public water supply. Backflow preventer valves find common use in commercial and industrial applications. Install a backflow preventer valve to safeguard your water supply and ensure uninterrupted access to clean water.

Everest Plumbing Nov 26, 2020
How does a backflow preventer work
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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.

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 an 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 avoid such consequences.

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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, known as backflow.

The pressure in the pipes can drop if the water within the structure overflows or the pipes freeze. The pressure changes in pipes can cause water to seep back into the main supply line and 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 the consumption of unsafe water.

A backflow preventer is a device plumber installs 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 public or private suppliers flows in one direction.

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 allow the flow of water through one way and then close when pressure comes back through. These valves have a spring device occupied by the pressure of the incoming water.

The way these devices work is simple. Therefore, when the pressure on the side of the main 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 prevent the backward flow of water. Besides, 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 its 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, shutoff valves are used 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. 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 DCV is effective against backpressure backflow and back-siphonage.

RPZ valves’ the safest and most 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 that 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 industry 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 is specially made for lawn irrigation systems in your home and 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 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 repair cost might be overwhelmingly high. Also, you might have to stay for days without water during the repair period and put 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 repair costs. 

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 professional assistance installing, inspecting, and repairing 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 a large selection of backflow prevention solutions for any application. Please feel free to contact us anytime.

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