You are not logged in.

Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.

Billw1

New Member

1

Thursday, October 5th 2006, 4:11am

Blow-Out Port

I would like to have a drain valve (winterization blowout port) installed on the outside (there is already a drain valve and shut-off ball valve in the basement) so that I would not need to be home for them to blowout the sprinkler system.

Do I have the drain valve installed outside <b>before or after</b> the PVB (backflow preventer)??? Which way is right, I've seen it done both ways? Is this drain value required for winterization? Is this a DIY project, will an irrigation company install this, or will I need to get a plumber?

Wet_Boots

Supreme Member

Posts: 4,030

Location: Metro NYC

2

Friday, December 1st 2006, 1:21am

Depending on your location, you may not want to add a thing. The original standard configuration would have a drain hose bib on the low point of the plumbing, just after it exits the house, and upstream of the PVB. Nowadays, this faucet could be frowned upon, as a possible cross-connection, where the codes are making the assumption that some idiot will hook up a hose and connect it to something nasty. One way around this is to use a simple PVC plug in place of a boiler drain faucet. Remove plug, connect air, winterize, replace plug.

It is more than likely that local service companies already have any adapters they need to connect their air to a PVB testcock, which means the indoor drain doesn't have to be utilized for winterizing.

Tom

Supreme Member

3

Friday, December 1st 2006, 5:08am

install the drain after the backflow. they can also use the test ports on the side of the backflow, but a threaded connection after the backflow is the preferred method.

Wet_Boots

Supreme Member

Posts: 4,030

Location: Metro NYC

4

Friday, December 1st 2006, 11:11am

Downstream installation has the advantage of not presenting the possible cross-connection that upstream installation does, but we always appreciated the convenience of having a low-point drain valve that was open all winter, so water leaking past the sprinkler system shut-off valve had a means to safely drip away, and prevent freeze damage.

SprinklerGuy

Supreme Member

5

Friday, December 1st 2006, 4:12pm

He already has a low point drain valve in the basement. We see it that way here in Colorado more often than not.
Sprinkler Solutions, Inc.
Arizona and Colorado
www.sprinklersolutions.net

Wet_Boots

Supreme Member

Posts: 4,030

Location: Metro NYC

6

Saturday, December 2nd 2006, 1:31am

The outdoor low-point drain would have the advantage of not dripping water into a basement, when left open all winter. Modern installs don't really have a good way to deal with a leaking system-shutoff valve, if it's passing any quantity of water.

Billw1

New Member

7

Saturday, December 2nd 2006, 3:55pm

Yes, there is a low point drain value already in the basement. Last year he needed to access this drain while I was home to connect this hose. By installing one on the outside, will a contractor be able to accomplish the same task? How is it normally done in the Northeast?

Rate this thread