Bill, Interesting that you mention the increased trip time. I just spoke with a dry valve manufacturer rep and he said the exact same thing. One particular system he was aware of went from multiple minutes (waterlogged) to seconds (not waterlogged). He also mentioned the potential for significant water hammer and an increased corrosion rate.
I'm hoping we can lower the supply pipe so there isn't any trapped water. Barring that, I'm going to suggest installing some type of automatic drain valve (to release water but not air). I understand there's at least one device that's listed for this use on the trim of the dry valve (but not remote from the dry valve). The engineer, AHJ and myself will have to discuss it. Ed Kramer Littleton, CO >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:sprinklerforum- >[EMAIL PROTECTED] On Behalf Of Bill Shipman >Sent: Wednesday, January 17, 2007 8:22 AM >To: [email protected] >Subject: Re: Dry pipe systems & trapped water > >Having spent 12 years installing sprinklers, 5 years in management, and >the >last 21 years designing them, I can tell you that the type of system (in >field personell terminology) is called "waterlogged". Any time that you >have trapped water in the system the trip time GREATLY increases. I've >seen >it happen many times. In fact, everytime after correcting the trapped >section of pipe, the trip time decreased to at least half of the previous >trip time. I can't explain exactly why, but it WILL happen. >-Bill _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
