I am working with a pretty simple model. A pump pumps water from a reservoir to the town and storage tank. There is no isolated transmission line, so pumped water meets the town's demands and fills the tank. When I run just the distribution system, I get no errors, however when I add in the pump and reservoir, I get the error: Pump cannot deliver flow or head. I followed the guidelines presented here (https://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/9025/user-notification-pump-cannot-deliver-flow-or-head) for troubleshooting and am not seeing any problems.
I will upload my model through the file share. I am working with the Dixon distribution and transmission scenario.
Wait, I think I see the problem now. 150 ft of elevation difference and only 95 ft of available head from the pump.
Yes, I believe that is the issue. With the downstream boundary (in this case the tank), the pump will try to balance the hydraulic grade at the tank. Since the initial tank elevation is higher than the maximum pump head, it will not operate and the warning will be generated. A pump that can provide more head should operate better.
Answer Verified By: Nastassja Abercrombie
Please note that I have added a diagram and paragraph to the Wiki article in question (User Notification "Pump cannot deliver flow or head") to help clarify this situation and how to understand/visualize it better in a given model.
Jesse DringoliTechnical Support Manager, Haestad ProductsBentley Communities Site AdministratorBentley Systems, Inc.