You are on the right track. Test and repair as needed, then flush. I had a similar situation in an aircraft hangar about 15 years ago. System froze and there were lots of issues. The occupant's first indication of a problem was falling debris, broken fittings. We went in and fixed the obvious issues. We then put air on the system and found several large leaks. Put air on it again and still had leaks but the pressure drop took much longer, so we felt confident to put water on the system (street pressure). Found several small leaks and repaired them. When system held street pressure, we pumped it up gradually to 200 psi. I think the whole process took 3 days. If I remember correctly, we also separated the system into smaller sections before we started testing, so as to help us locate leaks.
I would try to salvage as much of the existing system as possible, if only to help the owner save some money. Why discard the system because of what you think might be wrong. Find out what is actually wrong. System may be easily and confidently repaired or you may find enough issues or concerns spread out through the entire building to warrant total replacement. By proving this one way or the other you will be helping out the new owner. Mike Hill -----Original Message----- From: sprinklerforum-boun...@lists.firesprinkler.org [mailto:sprinklerforum-boun...@lists.firesprinkler.org] On Behalf Of Todd - Work Sent: Wednesday, November 20, 2013 8:02 AM To: sprinklerforum@lists.firesprinkler.org Subject: resurrecting an old system I am working with a company that bought a building where the sprinkler system had been turned off about 10 years ago. The fire department is requiring that a system be turned on. The existing system was fed from a pump taking suction from a pond (disconnected and removed). There has been some cracking and splitting of fittings at low points and some heads have popped. The first step was to have a contractor come in and made a detailed visual inspection of the system, including internal. That showed that all of the pipe up high appears to be in good shape and could possibly be re-used. However, there was some mud (not scale) that had collected in some of the mains. My thought was that the next step would be to fix or cap off the broken areas and do an air test to see what the integrity of the system really is, then flush the system if all looks good. However, would you want to flush out the mains before you do an air test? If there is a problem with the mains in the area covered by the mud, would the air test not show it? On the other side, flushing would create a problem since there is no public water supply. We would probably have to get a fire department pumper involved. Also, you could have an issue if the water finds a leak and water starts spraying down on equipment Thoughts? Flush or air test first? Todd G Williams, PE Fire Protection Design/Consulting Stonington, CT www.fpdc.com _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org