Usually a check is added above the preaction valve... Jeff Garrison On Dec 1, 2011 1:40 PM, "Morey, Mike" <[email protected]> wrote:
> We have what amounts to a closed head electronically actuated deluge > system, or maybe a non interlock electronically actuated preaction system? > I'm not even sure how to make the distinction. It utilizes a reliable > model B 6" deluge valve that appears to have more or less standard trim and > an alarm pressure switch. We're attempting to convert the system to low > pressure nitrogen supervision only to monitor the integrity of the pipe. > The issue we're running into is that when we attempt to pressurize the > system the ball drip/velocity check in the alarm pressure switch trim leaks > air at a high rate. The proposal was to add a check valve above the deluge > valve to allow an intermediate chamber without air pressure to be monitored > for alarms, but this adds another drain, pressure gauge etc that will all > have to be piped into 2 large and unwieldy systems that are already > installed. Is there anything that would prohibit us from just replacing > the ball drip valve with a standard d > rain valve, or adding a shutoff in front of the ball drip? These systems > are pretty meticulously maintained so draining off the alarm line wouldn't > be a major issue. Code wise I can't see anything that mandates the > presence of the valve, it seems to be more to allow condensate to drain and > allow the alarm line to be drained quickly after a trip. > > Mike Morey, SET, CFPS > Sprinkler Designer > BMW Constructors, Inc. > O: 317.651.0596 | C: 317.586.8111 > www.bmwc.com > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20111201/cac144ef/attachment.html > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20111201/54245d97/attachment.html> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
