If you are exceeding 877gpm, the building is probably already gone - or some burst pipe is taking up all of the water anyway. At that point, torching your diesel motor is probably going to be a lesser concern. Best case scenario is that someone drove their car into a standpipe, and a busted 4" is draining the pipes down. Someone would probably find out about that quickly enough to shut off the motor (hopefully!)
I am personally not a huge fan of suction control valves. That is just one more item that has the ability to shut off sprinkler flow to two entire apartment buildings. Unless the water company is worried about city-wide damage the water system, it seems like the greatest hazard/cost would be the buildings and the people in them. I would lean toward a more simple system. Matt -----Original Message----- From: Sprinklerforum <[email protected]> On Behalf Of Tom Duross via Sprinklerforum Sent: Tuesday, July 27, 2021 6:45 AM To: [email protected] Cc: Tom Duross <[email protected]> Subject: RE: FP Suction Control Valve I should have rambled a little more.. 750 gpm pump runs down to 20 PSI at 877 gpm (117%). Worried should water demand exceed that and cavitate the main and loose cooling water to the engine. Then we loose the pump house and the buildings. Residential areas are compartmentized so not as much worried about 2-4 heads going off but concerned about parking garages, standpipes and hydrants. Told local FD Capt. We would augment and ring hydrants per 291 and also placard stairways but wanted a fail safe to protect pump for down the road. FD is onboard including their outside PE. TD Why are you wanting to install the suction control valve? Was it requested by the FD or water supplier? I would be concerned about removing the PRV without knowing all about what is downstream. It would be just your luck that some contractor got a variance to build the mains out of pool-noodles that burst at 110psi... Matt -----Original Message----- From: Sprinklerforum <[email protected]> On Behalf Of Tom Duross via Sprinklerforum Sent: Tuesday, July 27, 2021 6:28 AM To: [email protected] Cc: Tom Duross <[email protected]> Subject: FP Suction Control Valve Good morning Campers. Looking for advice and comments. I have an existing diesel driven fire pump in a prefabricated pump house installed in 2012 serving 2 apartment buildings. I first tested this pump in 2017, had 13 hours on it, ran fine but we ran out of water at just about 100% capacity. Spent the day with the water department a few days later checking underground valves, flowing a few street main's hydrants, basically came to the conclusion that this is all we got. Wrote up a report, suggested they hire an FPE to see if the pump's tested capacity meets requirements, how did this happen, what about the hydrants off this system, stuff like that. I think I stirred the sleepy caldron a little. Didn't hear back from the client until this spring. Apparently they changed ITM contractors and the new one didn't pan out. They had a balcony fire May 2021, gas grille, 13R system with no attic protection, non-completed attic separations and fire walls, etc. Fortunately they had a response so quickly it never made it to penetrate the eaves and soffits and was extinguished between the 5th and 6th (top) floors. Local FD must have had a field day with a Q20 of about 800 and closest city hydrant ¼ mile away. Waiting for incident report to review. So back to my query. It's a xy&em pump house. All welded sch40 and painted. Not the greatest build as there's a 6" BFP vertically installed right off the incoming service with elbows turning it around and down to the floor to feed the pump. Just a few spacers in the piping so no room for slipping in this device unless something gets removed or moved. 4-15 of #20 (2013) says between the pump discharge and check and I get that but also defers to the mfgr. for direction. Looking at the various offerings most are a little vague on placement and even one says after the pump discharge valve. Without major surgery, I have 2 spots to slip in this 20" long device. I can remove the relief valve between the discharge increaser and pump check and put it there 'or' I can remove the tee feeding a 6" storz and check located between the discharge valve and the city bypass. The former will allow me to test through the device but the latter will not. I don't believe either of these appurtenances are necessary and I will explain (he's still rambling? Jeepers..). The engine is a small JD inline 4 running 3000 rpm, single ECM, max. speed is 3300. Churn is 155 at 3025. I haven't physically done it but if I extrapolate to 3300 I get 170 psi. I'm below 175 so I think the PRV can go. If I opt to remove the storz I can but testing this pump will have to be via the 3 hydrants it serves, in addition to the 2 buildings. I honestly don't know why the engineer (small E) had a storz included as this house it atop a hill in the woods ½ mile away from a city hydrant and these buildings. OK, done rambling. Loose the PRV or keep scratching my head? Let's go Red Sox! Tom Duross _______________________________________________ Sprinklerforum mailing list [email protected] https://linkprotect.cudasvc.com/url?a=http%3a%2f%2flists.firesprinkler.org%2 flistinfo.cgi%2fsprinklerforum-firesprinkler.org&c=E,1,mmPokZ5kJYxxqn-qLWYOa 8oByvhphYn0IWPvP-rwhJfnI61REB-9wquqpynEEdKJl0X271lXhFcIkVejTI97f_-715aBoh48o m2v3jREiFtX-eV7C0mR3iGd&typo=1 _______________________________________________ Sprinklerforum mailing list [email protected] https://linkprotect.cudasvc.com/url?a=http%3a%2f%2flists.firesprinkler.org%2flistinfo.cgi%2fsprinklerforum-firesprinkler.org&c=E,1,F_GSIi4FQnuM_GSrnPB_SGPFky-a8NaeA0vCwjgGL0R1ZTDKRDWkPYa_JCYFgW3rGN9nBebWdPn8vX6R9or_ltB2cwKiERaayM7gz_xEgjCewtc,&typo=1 _______________________________________________ Sprinklerforum mailing list [email protected] https://linkprotect.cudasvc.com/url?a=http%3a%2f%2flists.firesprinkler.org%2flistinfo.cgi%2fsprinklerforum-firesprinkler.org&c=E,1,9os33rJwEVuTAyT_HOBXRdYgsdVKl3G4wgsW_857-0TS6SZBR7YAY4VNJpmxWyy6KPTCyafA1dQbkZ43WOsKqFzAlGMSosGnmxkyc2u3VdDLlZrJ8ngs&typo=1 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
