Over-sized valve?

[nickolas]

Caution! Make sure your valve has the flow characteristics that you need in for both the cooling coil and then when it is in full bypass. We recently had to change out 2 valves, and I don't know all the details as I was just told about it, due to the bypass position not allowing enough flow - anyway one chiller serving two air handlers.

Good point; For that reason maybe the " 3 " inch valve would be more suitable in this case. (to insure required flow to the chiller in bypass). I think I have all the infomation necessary to select the proper valve.

One thing that I am sure of is, that the selection has not been "botched"

"Orion242--It will only be oversized if you botch the selection....."

Thanks guys I have learned a lot

[kontrolthis]

I am in no way a valve expert, but have picked up a few things along the way. If the pipe is 4" and you do place a 3" or even 2 1/2" valve in line, I know the Cv must be corrected for the piping reduction. It basically nets less Cv than listed flow for equal pipe sizing. Also a good point about the ball and characterizing discs. The bypass port on a Belimo (B) port is rated at only 70% of the A to AB port. Just a little reminder.