If you do not need the pump to meet the fire flow requirements of the fire code, than you can size it for the sprinkler demand only.
In evaluating any water supply, you do not have to add the outside fire flow to the building system demand in any case. In your scenario, it would not be a 2900 gpm demand it would be a system capable of delivering 2000 GPM at 20 PSI, or 900 GPM at whatever residual is required for the building system. Steve Leyton (Sent from my smartphone; please excuse typos and voice-to-text corruptions.) -------- Original message -------- From: Gregg Fontes via Sprinklerforum <[email protected]> Date: 4/21/21 6:57 AM (GMT-08:00) To: [email protected] Cc: Gregg Fontes <[email protected]> Subject: Fire Pump Sprk & Fire Flow Demand If a fire pump supplies both the fire sprinkler system and the site fire hydrants, does the fire pump gpm need to be capable of suppling both? (Fire sprinkler demand 900 gpm and site fire hydrant demand 2000 gpm for a total of 2,900. Can the fire pump be size at 750 for the fire sprinkler/hose demand or does it have to be a 2000 gpm so it can supply both the sprinkler and site fire hydrant flows of 2900 gpm?) The supply is city water and there is a bypass on the fire pump. The city supply comes into the fire pump house and goes out to single loop that supplies both the fire sprinkler systems and the site fire hydrants. (The city flow and psi is adequate to meet the site fire flow at 20-psi.) Thanks, Gregg Fontes _______________________________________________ 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
