Been lurking for a while... We have the 911 room for Boston Police at their headquarters and after draining each and every return-bend head off their 2 preaction systems last year, we installed a shut-off. The client was very nervous about having ANY water in the drops, even under 30 PSI of air. You have to trip these valves so everything will get wet (inside). Not a direct answer to the original post but even if I could, I wouldn't use return bends where main frames, media, etc., are located. TD
-----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Lamar Vaughn Sent: Tuesday, March 17, 2015 8:42 AM To: Sprinkler Forum Subject: Re: Pendent sprinklers on return bends on a pre-action system Sean, this may not be so much a code issue but an equipment protection issue. The reasoning for the pre-action system is to protect what is in the room from a potential leak of water. I have always been required to use the dry pendent drops in these applications for this reason. Nothing to do with freezing. My opinion. Lamar Vaughn, SET On Mon, Mar 16, 2015 at 10:03 PM, Sean Lockyer <[email protected]> wrote: > Even though (non-dry) pendent sprinklers must be installed on return > bends on dry systems what about pendent sprinklers in a > heated/conditioned space that is protected by a double-interlock, > pre-action system (such as a video production room, etc.) ? > > Does the fact that it is above a conditioned ceiling space matter ? To > my knowledge there is nothing in NFPA codes or the manufacturers > listing that give you an allowance for special situations like this > but I was wondering if anyone else has any experience with this sort of issue ? > > I would like to hear everybody's thoughts.. > > > Sean Lockyer > Project Designer 4617 > Parkbreeze Court > Cell 386-279-1197 Orlando, > Florida 32808 > [email protected] Phone: > 407-816-9101 > www.AITLifeSafety.com Fax: > 407-816-9104 > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkl > er.org > _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
