George, I have designed several pumps with flow meters and never put a check valve on the discharge side of the meter. Looking at NFPA 20 (2007) Fig. A.5.19.1.2(b) does not indicate a check valve in the test loop. So if this is a requirement it is news to me. The meters we use are a venture type, so backflow shouldn't cause a problem as there isn't anything to damage. Are you using a turbine type meter?
Jim Johnston, P.E. Fire Protection Engineer Inland Fire Protection, Inc 1100 Ahtanum Road Yakima, WA 98903 Phone 509-248-4471 Fax 509-248-1180 [email protected] -----Original Message----- From: George Medina Jr [mailto:[email protected]] Sent: Wednesday, March 18, 2009 2:04 PM To: [email protected] Subject: Check Valve On Discharge side of Flow Meter NFPA No.:Z4Pump02 page 108 - States that a check valve is required on the discharge side of flow meter. Our union field guys state they never put one on?there. Is this correct? I believe a flow meter would be damaged from positive city pressure back flowing through the meter after shutting down the pump and before closing the isolation valve. Somebody correct me for being wrong. George Medina Jr. Sr. Fire Sprinkler Designer Dorvin D. Leis Inc. Honolulu, HI 96819 _______________________________________________ Sprinklerforum mailing list http://lists.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) _______________________________________________ Sprinklerforum mailing list http://lists.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)
