Plumbing in the Home/Backflow replacement


Hi Louie,

Thanks in advance for volunteering. The body of the backflow preventer to our lawn irrigation system froze over the winter and I'd like to replace it myself. I'm a do-it-yourself type. It's a Wilkins 975XL 3/4". The replacement part comes with the valves. Right now I have both valves in the off position. When I take off the cracked backflow preventer and the old valves, is water going to start spraying? I'm just wondering how the water will stay off if there's no valves on there to stop the flow. If I turn off the water running into the house does this also turn off the water outside the house? Anything else I should know before I start?


You have to turn the water off at the street first. The valves and the backflow are one complete assembly and not made to be taken apart separately. So turning the main off, which is normally at the street, would have to take place, thus allowing you to cut the waterlines. I hope that helps.

Plumbing in the Home

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Louie The Plumber


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