Best location for control valve inlet or outlet?

[MechEng92]

Where is the best location for a control valve in a chilled water system, on the inlet or outlet of the cooling coil?
I recall reading somewhere that outlet is better as it provides a full coil of liquid at all times and temperature change reacts better to cooling demand.

Thanks

 

[Artisi]

Outlet.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[LittleInch]

It's a closed pressurised system?
This shouldn't allow any part of the system to fall below a certain pressure so you're not going to get any draining or air in the system
Then it makes virtually zero difference.

Inlet the system will see a slightly lower pressure, but should still be capable of seeing full design pressure
Outlet then coil will always be packed at inlet pressure.

Just make sure the flow direction on the valve is correct!

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

 

[MechEng92]

Thank you, it will be a closed system.
What is the benefit of it being on the outlet? Does having a full coil prevent noise from water hammer? Is there quicker temperature control response?

Thanks

 

[LittleInch]

On the assumption that it is
a) A closed system
b) The cooling coil is fully vented and full of water

What is the benefit of it being on the outlet? - There isn't one (IMHO)
Does having a full coil prevent noise from water hammer? - NO
Is there quicker temperature control response? - NO

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

 

[EnergyProfessional]

hydraulically it doesn't' matter in a closed system.
the small advantage of locating it at the outlet of a hot or chilled water coils is a bit less extreme temperature at the valve, and little less pressure.

 

[MechEng92]

Excellent, thanks very much EnergyProfessional