Buffer Vessel Location

[antigravity1989]

Hi there,

Got a primary/secondary chilled water system that for a large server room which is currently cycling too quickly, a buffer vessel was included in the original schematics but has not been installed for some reason. Is it best that the buffer is located in the primary return as a simple buffer or in the flow as a thermal storage unit?

[The Viking]

There are lots of theories, no doubt we will see a few of them in this thread in the next 24hrs...

However, the lower the temperature differential the less temperature migration there will be.
So if we see the ambient as a constant then in your two options above there will be less temperature difference between the media inside the tank and ambient if the tank is on the return (and therefore less heat gain).

Opening up a whole can of worms here but another option would be to have a divided mixing tank, a tank with a wall in the middle that leaves about an inch or so free area (normally either at the top or bottom) between the two halves. The primary circuit supplying the A side of the tank and getting it's return from the B side with the secondary loop sucking from the A side and discharging to the B side, a big open header if you like...

:cool:

[frank]

Normal practice for a buffer vessel is to put it in the return to iron out temperature fluctuations, which works well if the chiller control is on return temp. If the chiller control is on leaving water temp, then this configuration won't help.