I've run into the same issue in a large industrial plant with two dry pipe valve, a plumber with many years of experience offered this his advice on quickly finding leaks:
1.Use liquid Fluorescent Green Tracer, add about 1 ounce to the dry pipe valve, mixed into priming water. 2. Allow the system to charge with air , then trip at the furthest inspectors test point or drum drip from the DPV. 3. Open each drum drip and test valve to ensure the tracer dye is in contact with all piping in the system 4. Allow the system to remain pressurized with water for about 15 min. 5. Use a ultraviolet light source to located the leaks. ( Works much better if you can turn off the lights, in a darkened warehouse I could spot leaks from the floor to the pipe, 35 feet AFF) Note: A. The dye is EPA registered and can be flushed into the sewer system or left to evaporate on a parking lot without concern about ground water contamination. B. The dye is very concentrated, 8 ounces will treat 6,000 gallons of water. C. Available from: Black Light World PO BOX 26 Cub Run, KY. 42729 Fax: 270 721-0073 E-mail: [email protected] Website: http://www.blacklightworld.com/index.htm Hope this helps, Yours truly, FRANK J. HERRICK CITY OF LEAWOOD FIRE DEPARTMENT OFFICE OF THE FIRE MARSHAL 14801 MISSION ROAD LEAWOOD, KS. 66224-9560 -----Original Message----- From: Letterman, Todd [mailto:[email protected]] Sent: Monday, March 01, 2010 11:11 AM To: [email protected] Subject: RE: NFPA 25 Dry system leaks It has always been my experience that most leaks are at the valve, compressor, or drip drums if it has one, this is where I would start first. Todd Letterman Fire Protection Engineer SET CFPS Riverside County Fire Department "Fire never sleeps" (951) 955-5273 FAX (951) 955-4886 [email protected] " Life is not about waiting for the storm to pass but learning how to dance in the rain" -----Original Message----- From: Forest Wilson [mailto:[email protected]] Sent: Monday, March 01, 2010 7:33 AM To: [email protected] Subject: NFPA 25 Dry system leaks We have a 20000 sq ft wood building, dry system in attic and below ceiling. It has several small leaks, loosing about 5.5 psi air per hour. I don't have 25 in front of me, but I recall a 24 hour air test is done to ensure system holds without tripping at 5 year intervals. We have to cut holes in the drywall ceiling to access many of the pipe joints. Since everyone is on a budget, I was going to suggest to the owner he could have us do this work in a 3 year timespan, one third of the building per year replacing leaks as found during a thorough inspection. Does this sound acceptable? Forest Wilson Project Manager Cherokee Fire Protection Co. 1855 Bellbrook Ave. Ste C Xenia OH 45385 ph: 937-376-2333 fx: 614-455-4324 cell: 937-307-5647 . Visit our blog: www.cherokee-fire.blogspot.com NOTICE: The information contained in this email is intended to be solely for the use of the named individual or entity to which it is directed and may contain information that is privileged or otherwise confidential. It is not intended for transmission to, or receipt by, anyone other than the named addressee (or a person authorized to deliver it to the named addressee). It should not be copied or forwarded to any unauthorized persons. If you have received this electronic mail transmission in error, please delete it from your system without copying or forwarding it, and notify the sender of the error by reply email or by calling Cherokee Fire Protection Co. at 888-347-3079 toll free. _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
