I recently inspected a wet sprinkler system. It was installed in 1997 and had not been inspected or tested since installation. I conducted a main drain test. The residual pressure was 30 psi. Static 75. According to the hydraulic calc plaque, the residual should be 60. The gauge was downstream of the main drain, approx 80 feet of pipe downstream.
I sent a Notice of Impairment to the owner and requested a copy of the Contractors Test Cert to use as a benchmark. The installing contractor told the owner: the pressure gauge is installed in the wrong place and the system is fine. Any thoughts? Forest Wilson Fire Sprinkler Contractor 937-736-0425 Notice: This message is confidential. It may also be privileged or otherwise protected by work product immunity or other legal rules. If you have received it by mistake, please let us know by e-mail reply and delete it from your system; you may not copy this message or disclose its contents to anyone. Please send us by fax any message containing deadlines as incoming e-mails are not screened for response deadlines. The integrity and security of this message cannot be guaranteed on the Internet. -------- Original message -------- From: Tom Duross <[email protected]> Date:12/06/2013 6:02 PM (GMT-05:00) To: [email protected] Subject: RE: NFPA 13D Water Supplies Dude, I believe every tank system has refill whether off another pump and tank, or traditional domestic. We do pumps and tanks all over Boston (13D up to 3 family but 20 minute supply per Maurice P.) mainly because the purveyors are so expensive with permits, bonds, tap fees and pipe rentals that Owners have spent the cost of the tank system before they dig a hole. I believe you also have to factor in domestic usage so refill may not be as great. I've never taken a credit for it because I'm leery of degradation of the pumps over time. I will say SPP (and others) make good 220/1 pumps but I'd advise using a SS fitted pump rather than CI, about $75 more for the typical 2 HP end suction variety. I would also advise getting a pump control panel too. CH makes a nice one sold through RH Stearns in Portsmouth, NH. It has an off-delay which helps with hammer prevalent in these systems and will also drive a bell or horn/strobe and has dry contacts for Fire Alarm. One thing I did with the last two I bought was to install a run timer, $50 from Grainer, 1 yr. battery, and runs the pump once a week for 10 minutes. Keeps it working. One other thing, install a low pressure switch on the riser and connect as alarm. That way if you lose power and have no water supply and a head opens, the alarm still rings through its batteries and people get out. Dude Folks, Been watching the thread and wanted to chime in a little as Mr. Huggins, PE has done. Any 220V pump and any tank that will hold water are an acceptable supplies in areas served by well water. And when sizing the tank, you may use the water supply's refill rate to eliminate some of the gallons required to be stored. So on a home with a well pump (that probably already has it's own pump and pressure tank), you can branch off of that supply and fill a tank. That tank can be sized like so: Demand gpm X 10 minutes = Total Water (in gallons) Home water Supply gpm X 10 minutes = Total Refill (in gallons) Total Water MINUS Total Refill = Tank Size Two sprinklers (YES! ONLY CALC 2 IN THE BASEMENT) x 10 minutes usually equals less than 300 gallons total. Subtract 100 gallons or so for refill and you only need a 200 gallon tank. A 6ft tall, 30" diameter tank (fits through a 32" door), will suffice (+/- 220gallons). A 2HP pump can handle this (up to 45 psi). See SPD Pumps for some really good charts and products.http://www.spdinc.com/products/residential.html (Or call and talk to Dave and tell him I said, "YO!") This is a very inexpensive solution for a rural home. It should be recognized that the above is my opinion as a member of the NFPA, and has not been processed as a formal interpretation in accordance with the NFPA Regulations Governing Committee Projects and should therefore not be considered, nor relied upon, as the official position of the the NFPA, nor any of their technical committees. Sincerely, Cecil Bilbo Academy of Fire Sprinkler Technology Champaign, IL 217.607.0325 www.sprinkleracademy.com [email protected] OUR STUDENTS SAVE LIVES!! _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
