Go Back  DoItYourself.com Community Forums > Garden and Outdoor Center > Lawns, Landscaping and Outdoor Decor
Reload this Page >

backflow preventer leaking with house water shut off

backflow preventer leaking with house water shut off

Old 11-23-15, 06:59 AM
Thread Starter
Join Date: Nov 2012
Location: usa
Posts: 29
Upvotes: 0
Received 0 Upvotes on 0 Posts
backflow preventer leaking with house water shut off

I've got a confusing situation. We had the sprinkler system winterized and the backflow preventer is still leaking a little even though the house water line to the sprinklers is off.

I thought maybe the valve inside the house was broken and allowing some water through, but when I open the spigot inside a little air is released, but no water. When I open the outside spigot an ounce or two drains out. the inside shutoff and spigot are below ground level.

This sounds weird, but could there be something that is causing pressure to build up in the sprinklers and push water from the yard back towards the house?

Name:  inside.jpg
Views: 1906
Size:  29.3 KBName:  outside.jpg
Views: 7107
Size:  49.6 KB

Old 11-23-15, 07:15 AM
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 26,808
Received 1,953 Upvotes on 1,749 Posts
It is extremely difficult to get all the water out of the lines so some water is not that unusual. As for the pressure how much is there? Changes in temperature and atmospheric pressure could force water back to the house but not with a lot of pressure. It's possible that there is pressure in the lines if they used compressed air to blow them out for winterization.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: