you should have packed your bags after the first test. You are only looking for the Q to meet or exceed the flow portion of the system demand.
Roland Roland Huggins, PE - VP Engineering American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives Dallas, TX http://www.firesprinkler.org On Jun 23, 2013, at 1:22 PM, Douglas Hicks <[email protected]> wrote: > We a forward flow at a church last week. When we did the main drain flow > test we got 30 PSI. We tested through a single snoot FDC, with the FDC > check valve turned around, the clapper valve was not removed. > #1 forward flow test with 1.5” nozzle. We got 24 PSI, 337 GPM > #2 forward flow test with 2” nozzle, 16 PSI and 493 GPM > # 3 forward flow test with 2.25” nozzle, 12 PSI and 536 GPM > The above results were with a straight fixed nozzle > > The hydraulic name plate > Design Density .10 GPM > Area of operation 917 Sq Ft (the sprinkler protects the basement, which > houses a day care, 2 bathrooms, janitor closet, mechanical room, elevator > room, and a hallway. > System demand at bottom of riser 242.8 GPM at 59.95 PSI > Water supply flow test, 84 PSI static, 70 PSI residual flowing 981 GPM > > > The water flow comes through the wall, 6 inches off the floor, makes a 90°, > up through the backflow device, through the 2.5 inch alarm check valve, 3 > more 90° to the single snoot FDC. Then through the wall and our flow tester. > The water was clean after 1 minute. We did not do a comparison with a > certified gauge, nor did we replace the gauges on the wet pipe. > > The chart is supplied with the flow tester. > > Do these results look legitimate? A larger nozzle = more GPM and less PSI? > _______________________________________________ > 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
