Chilled Water Air Separator - Is It Needed?

[BronYrAur]

Just looking for opinions on whether or not air separators are needed on chilled water systems. I have always used them but have lately been hearing that they are not really needed.

 

[UtilityLouie]

I've always used air separators in chilled water systems as well.

I think that during start up and complete system refilling, you probably need it (unless you have a dedicated person to purge air out of the system for a few weeks).

I think it's the same way with HW systems... during start up and system heating, you really remove a lot of air because HW cannot hold as much air as the water at the fill temperature... but when the system comes to equilibrium the air separator doesn't need to work anymore. If the separator still is working, your system corrosion would be incredible!

 

[KiwiMace]

I consider this an issue of topography.

I use them where the system is a flat sprawl. Industrial plants typically get them.

I have not normally used them where there is a reasonable elevation in the chilled water system, in commercial high rise. I just put an automatic air valve at the high point of the system.

 

[quark]

I agree with CinciMace. I have never used any.

PS: Thermostatic traps can be good and cheap air purgers.