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Backflow Prevention

When the direction of the flow of water reverses on its own in a pipeline or plumbing system, it is called backflow. This is not a favorable situation and backflow can be dangerous because it can lead to drinking water from a plumbing system becoming contaminated and unsuitable to use. To prevent backflow from happening, mechanical plumbing devices known as backflow preventers are usually installed in plumbing systems When dealing with backflow preventers, many people often have questions due to not having the knowledge that they need. Experts often are needed when dealing with backflow preventers as well as installing a backflow. Listed below are a few questions answered by the Experts on backflow problems.

I did not leave my Watts backflow preventer outdoors during the winter and reinstalled it recently. Yet, it has now started dripping on my irrigation system. What can I do?

It sounds like you may have to rebuild the backflow preventer if it is leaking. You could attempt to dismantle it and clean it but since the gaskets in the rebuild kit would be needed to do this, it may be better to just rebuild it anyway.

When my backflow preventer started leaking, I turned off the water. Once the water was turned on again, it started leaking from the vent. Would you know why this is happening?

It seems like you have a Reduced Pressure Zone (RPZ) backflow preventer and a faulty check valve is probably what is causing the problem. There are two choices you have here. You could either call a professional plumber to examine the valve and fix it if it is an RPZ or, if the device is situated on the supply line to the hot water boiler, it may need to be replaced. If you choose the latter option, you may be able to do it on your own.

My backflow valve on the outdoor sprinkler system froze and burst. Do I need to turn off the leaking water or just leave it running to prevent the pipes underground from freezing?

It would be better for you to shut the system down. If there is any water left in the underground lines, it should be warm anyway because of the higher temperature below the ground.

I switched off the main water valve in order to replace a sprinkler system backflow. But once I started cutting through the PVC pipes, I found that water was spewing everywhere. The sprinkler system valves were also turned off. What do you think is the reason for the water flow?

This doesn’t seem like a serious problem and would probably depend on the kind of sprinkler system you have. If it is a wet sprinkler system, the pipes would be filled with water and would possibly take a longer time to fully drain.

A leaking backflow preventer should be fixed as soon as possible. To begin with, it is first important to correctly diagnose the problem. If you’re not sure how to diagnose the backflow preventer problem, or are not sure how to fix it once its diagnosed, consult an Expert to help answer your questions.

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