How to acurately determinng flow rate

Hi,

Posted here several times before and am amazied by the excelllent help and advice. Thanks.

I have a newly installed system that is giving me fits. First off it is way oversized.
I do not see the D/T's that are expected and suspect flow rates in both the primary and secondary.
Some of the zones have hidden plumbing in my old, 1860, home and determining the head is difficult.
Is there a way to accurately read flow rates in zones and in the primary circuit?
Are there pumps that you can dial in the desired flow rate? I see the Grundfos 15-55 shows a GPM reading on the face, but don't seem to read in the specs that you can actually dial in the gpm you want. There are flow meters but it seems they have to be plumbed into each line/zone. Costly and time consumig.

Thanks for any advice.

Tom

Who installed the system?

Most must rely on temperature differential and pipe size to fix the flow. Some ModCons can be adjusted for gross output. The problem often lies in minimum unfortunately. We will need pictures, zones, boiler etc.