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 ...

For example, they are used to prevent boiler water, which may contain anti-freeze, from contaminating water supplies. Backflow preventers use several types of check valves. Swing check valves have a ...

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.