The idea is to get out a majority of the trapped air but not every bit. So in your case you don't need to tie in every sprig and have multiple air vents, you could put it off one of the back sprigs but a remote branch line works too.
The other option is to use AGFs in line vent that you can put near the beginning of a system and it supposedly gets the air out before it has a chance to form pockets downstream. Haven't used one yet but they seem cool On Fri, Mar 6, 2020 at 1:33 PM Bob Knight via Sprinklerforum < [email protected]> wrote: > In this case, the branch lines are all located beneath the trusses. The > trusses are shallow open web wood two feet on-center. The elevation is > 11’8” everywhere, so the sprigs are actually the highest points. That > said, it sounds like the air vent just needs to be at the furthest point > that it can be. > > > > > > Thank you, > > > > Bob Knight, CET III > > Fire by Knight, LLC > > 208-318-3057 > > > > *From:* Sprinklerforum [mailto: > [email protected]] *On Behalf Of *Steve > Leyton via Sprinklerforum > *Sent:* Friday, March 06, 2020 10:52 AM > *To:* [email protected]; [email protected] > *Cc:* Steve Leyton > *Subject:* RE: Air Venting > > > > I’d put it on a branch along the highest part of the building to which > piping is attached, assuming that the piping more or less follows the roof > contour. > > > > SL > > > > *From:* Sprinklerforum [mailto: > [email protected]] *On Behalf Of *Bob Knight > via Sprinklerforum > *Sent:* Friday, March 06, 2020 9:21 AM > *To:* [email protected] > *Cc:* Bob Knight > *Subject:* RE: Air Venting > > > > Thanks Steve. I get the high point part. This system is all one > elevation, but sprigs are being used. Do I put the air vent on one of the > sprigs, and is the most remote branch line the appropriate location? > > > > > > Thank you, > > > > Bob Knight, CET III > > Fire by Knight, LLC > > 208-318-3057 > > > > *From:* Sprinklerforum [mailto: > [email protected]] *On Behalf Of *Steve > Leyton via Sprinklerforum > *Sent:* Friday, March 06, 2020 10:17 AM > *To:* [email protected]; [email protected] > *Cc:* Steve Leyton > *Subject:* RE: Air Venting > > > > Usually - and I mean to say, almost always – that’s going to be the high > point of the system. Trapped are generally migrates to the high point > eventually. There are exceptions and some piping configuration can trap > air in pockets that aren’t at the highest point of the system, but that’s > usually where it is. > > > > > > > > > > > > > > *From:* Sprinklerforum [mailto: > [email protected]] *On Behalf Of *Bob Knight > via Sprinklerforum > *Sent:* Friday, March 06, 2020 9:11 AM > *To:* [email protected] > *Cc:* Bob Knight > *Subject:* Air Venting > > > > Not being an air venting expert, when NFPA 13 (2016 ed.) says “The air > venting valve should be located where it will be > > most effective. System piping layout will guide the designer in choosing > an effective location for venting. In order to > > effectively accomplish venting, it is necessary to choose a location where > the greatest volume of trapped air is vented > > during the first fill and each subsequent drain and fill event (A.8.16.6).” > > > > No other guidance is provided, so would this be at the most remote branch > line, or at the end of a dead end main, or somewhere else? > > Is there a “best practice” that is being used? > > > > Thank you, > > > > Bob Knight, CET III > > Fire by Knight, LLC > > 208-318-3057 > > [image: FBK-LOGO-EMAIL] > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > -- Benjamin Young
_______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
