Plumbing Design

[atlantis103]

Current customer in the process of retrofitting constant pressure system with VFD. Current system has two Aurora 421 pumps that operate independently of each other 24 hours a day. Plumbing in the 20 story building steps down in size starting with a 6 inch main. The Riser (off the main) begins at 2 1/2 inches and reduce in size as they go up into the building terminating with a 1" pipe. There are no pressure reducing valves in the building other than Cla-Vals at the pump outlets.

Does anyone know what type of system this is and what negative effects can be expected when retrofitting to the VFD?

 

[bimr]

The type of system is the basic high rise setup.

You can do these systems with VFD's or constant speed pumps with mechanical pressure controllers. Either work fine.