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

All Answers

Answers by Expert:

Ask Experts


Louie The Plumber


I can answer any questions. Period.


I am a 35 year Master Repair Plumber. I have owned my own repair company for over 20 years. My company has been the number one rated company on Angie's List for 5 years in a row. I have received the Angie's List Super Service Award for 5 years in a row. We are also the mosted rated company. We have almost a straight A rating across the board (99%) A's.

Angie's List

Master Plumbing License since 1987

©2017 All rights reserved.

[an error occurred while processing this directive]