I think it was George Church or Ron Greenman who had a way of finding leaks in dry pipe systems by putting peppermint oil in the DPV and then pumping up the system with air. Follow the smell in the attic back to the leak(s). Never tried it myself, but would like to know more about how to do it and how well it works.
Long term, you are looking at replacing leaky pipe and/or figuring out how to convert the system to wet. *Dave* On Mon, Dec 12, 2011 at 5:04 PM, Tom Duross <[email protected]> wrote: > This is kind of a rant/long winded digression/request for opinion kinda > thingy.. > I have a group residence built in the late seventies with a dry system. > I-2, ranch style building with attic. > Steel pipe, attic and living space coverage, 13 design (closets, bathrooms, > concealed spaces, everything covered). > I've mentioned it to this forum before. The dry system has become a real > source of frustration this past month. > When we did our annual testing this summer all went well. This is our 3rd > year here so we did a full flood trip. > Been fine as far as I know since August. This past Saturday it tripped. > When I got there, reset it, noticed air pressure dropping and air > compressor > cycling every 30 minutes. > I climbed into the attic (more like lumbered) and found several locations > of > pinhole leaks in the underside of mains. > This is old 2 1/2"-3"-4" threaded pipe sitting on the bottoms of the > trusses. Great. > With it being a Saturday afternoon, the supply house is closed. > I managed to find a couple of plumbing supply houses ready to close and > bought three saddle type repair clamps. > Went back and installed them and once back up, the cycling dropped to about > every 90-100 minutes for about a 20 minute run. > I tightened up the differential on the pressure switch so it ran for only > 3-4 minutes but it started every 45 minutes or so. > I felt that better since it was a riser mount and got hot in that 20 minute > cycle. > The clients were all still out at a day program and needed to return, > feeling for them as I do I told the manager to bring them home. > I called the Deputy, told him I did a temporary patch and fix for the > weekend, pretty sure it would be OK, and would return Monday. > I returned Monday morning, still cycling every 45 minutes or so, squeezed > back up (with some lights this time!) and found one more. > Right under the pipe, as you slide your hand along the pipe, just a little > hiss of air. I had brought gas leak detector with me in a spray bottle. > I sent baby brother out for another repair saddle (I just wanted to get it > tight first) while I balanced across 24" OC roof joists with a trouble > light > in one hand and a flashlight in my mouth. I sprayed every fitting I could > see, even the high uprights, no bubbles. We put the 2" saddle on, > compressor started and stopped, we sat there in the attic for over an hour, > quiet as church mice. About ready to get up and pat each other on the > back, > the air compressor started again. UUGH! We climbed back down, watched the > gauge again, sprayed half a bottle of leak detector all over the dry pipe > valve, air supply, inspectors test, went in and sprayed the faces of the > dry > pendents. That's all that was left. Nothing found. > I think I'm just almost causing small leaks to appear after I stop the > larger ones. Almost chasing my own tail (if I had one). > Remember Curly standing in the bathtub putting one section of pipe into > another and the water won't stop? Am I a victim of circumstance? > > Well, it's still this way as I write this and thinking of options for the > Owner, I wanted to (get to the point Tom) run something by the forum. > I'm past the point of no return weather-wise, I don't want to flood it. It > was 28 degrees last night. > What if I pumped glycol (I know, I know) to not only maybe find a drip but > maybe to stabilize it for the winter? Has anyone done this? > The other question, and the reason behind the title, could I just abandon > the dry system? > Could I just change the system from a '78 NFPA 13 dry system to a '07 13R > in > an existing building that's already sprinklered? > The attic isn't used for living purposes, storage, has no mechanical > equipment or anything serviceable. Just an 18x18 access panel. > I think if it wasn't sprinklered and I was asked to install a system, > that's > what I'd do. A soffitted wet system with sidewalls. > > Scratching my head and removing splinters. > > TD > > _______________________________________________ > 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/20111212/12c45b59/attachment.html> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
