Backflow Preventer Testing, Repair and Installation Services


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What is Backflow?

Backflow is the unintended flow of water in the opposite direction in your pipeline or plumbing system. Backflow is dangerous because it can cause contamination of clean drinking water.

Types of Backflow

Occurs when the downstream pressure exceeds the pressure of the water supply distribution system. A decrease in water supply pressure can also cause backpressure. A decrease in water supply pressure occurs when the amount of water being used exceeds the amount being supplied. A decrease in water supply pressure can occur during water line flushing, fire fighting or water main breaks.

Occurs when there is a partial vacuum in a water supply system, which draws water from a contaminated source to the potable water supply. High-flows out of the distribution system such as in the case where a pump is connected to a fire hydrant during firefighting can cause a significant decrease in pressure around the withdrawal area causing backsiphonage. The same conditions can be caused by a water main break. Another cause of backsiphoning is an incorrectly installed toilet without a plumbing-code approved toilet ballcock that provides an air gap that prevents contaminated water to backflow to other water outlets.

What is a Backflow Preventer?

A Backflow Preventer is a device that consists of a pair of mechanical check valves that prevents contaminated water from flowing backwards into your property or public water mains. It takes unsafe water that may contain chemicals, pesticides, feces and other hazardous materials that may cause health risk, and diverts it away from your property, keeping the unsafe water from re-entering.

Most municipal codes and water utility companies require backflow preventers installed to protect the water main lines from contamination. The average homeowner should have a backflow device for a lawn irrigation system or for a boiler heating system. If you don’t have one on either of these devices, you could be putting yourself and family at risk of getting sick or worse. A defective backflow device in a boiler heating system could be very dangerous. Since water expands when heated, contaminated water could be pushed back into the home and into the potable water system.

Backflow Testing and Maintenance

To keep up with local code, backflow valves must be inspected annually to make sure that your device is working properly and efficiently. In Missouri, most municipal codes require having your backflow device inspected every two years. It is crucial to have your backflow device tested to ensure the safety of your drinking water, for you and your family. You can trust our licensed plumbers at Bieg Plumbing to test your backflow device for commercial or residential applications.

Bieg Plumbing Backflow Prevention Services include:

  • Installation of Backflow Prevention
  • Devices
  • Water Testing Solutions
  • Maintenance
  • Repair Backflow Preventers
Bieg Plumbing has over five decades of experience in installing and testing backflow preventers. Our clients include industrial, commercial, municipal and residential. You can trust our highly trained and knowledgeable personnel. Do not take any chances with your drinking water. Call (314) 487-4564 for one of our experts today to schedule an inspection for your backflow device.



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