Closed loop chilled water system

[AstroHouse]

I have been at logger heads with the designers for the past two years, my system has expansion vessel, degasser and pressurisation unit, my highest point is 10 mtrs and my lowest ground level. I have 3 turbocor chillers but only use 1 as my load is approx 280kw with a total design load of 740Kw. I have N+1 on my secondary pumps which means I run 2 at a time. My problem is that they insist that I run at a pressure of 5.2 bar and for this my pumps are running at 90% (which seem to leave me no room to take up the remaining 480kw of load. I would have thought this pressure much too high if the frictional losses had been calculated correctly. also my suction pressure is 2.3 bar and my discharge is 5.2bar.
this has been driving me crazy for the past two years as I have sever starvation in certain parts of the system which was supposedly balanced, but the balance sheet shows most of the DRV's as being 100% open and 13% of design flow.

I believe this could be a long post and any help would be gratefully received

 

[LittleInch]

Hmmm,

I think you really need to draw this out in a schematic so that we can understand the key issues. This includes notes of flow, pressure, temperature and power where you have them. when you say 90% on your pumps, 90% of what? power, flow, head?

How many pumps are there?

You seem to have two systems - primary and secondary, but I can't work out which is which.

DRV's? please expand the abbreviation so we don't guess at what it is.

I'm not sure exactly what your issue or problem is but it is clear you have one. Take a breath and step back and think how you can get what you see in front of you onto a schematic and some words on both the operation and what the key issue is for you, then we might make some progress, but at present there is about 10% of the required information.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[AstroHouse]

Many thanks for the initial response, I will get a copy of the drawing.
Sorry DVR double regulating valve made by Crane to regulate flow.