Backflow preventers use several types of check valves. Swing check valves have a closure element that is pushed aside by the flow, but that swings back into the close position when the flow is ...

The check valve permits free flow in one direction and no (checked) flow in the opposite direction. This valve is specified in many applications because of its very low cracking pressure (typically ...

Sewer backflow preventers are an essential part of your home's plumbing. Here's why you need one and how to test if yours is ...

Find his work on sites like Angi, USA Today and The Pen... Backflow preventer installation costs between $105 and $1,400, with the average property owner spending $325 per backflow preventer.