Pump to air purger relation

Brad White_203

but where the expansion tank is connected that counts.

Ideally, the air purger (air separator to some), wants to be on the suction side of the circulator and into that, so it just happens, is a connection for the expansion tank or tanks.

The point of no pressure change, technically the lowest pressure at that elevation, coupled with the hottest water means the greatest air release, which is why that location is favored. That is the air removal side.

So if both are on the suction side, all the better.

Now, you <i>could</i> install the air purger downstream of the circulator I suppose. I will work "ok" in that function, but the expansion tank should always be connected directly upstream from the circulator.



As for the "why", that is contained in "Pumping Away".

Kurt Peterson

hydronic pump to purger relation

Pumping away from a cast iron vent dampered gas boiler.
Is the location of the air purger critical? I have always put it on the outlet side of the pump (probabaly 50 installs) never had a problem. I thought that I learned that reading "Pumping Away" Am I wrong? Does it matter? If so why?
Thanks

Bob Bona_4

it all

matters. If you have read "Pumping Away" then you know the main thing is that you are pumping away from the PONPC to add to the system pressure to keep air in solution.

For tradition,consistency,and convienience,your water feed should be at the PONPC, which happens to usually be at the air scoop. Which has 1/2" tappings for the x tank,the feeder, and a Hyvent if not using a Spirovent or some such. How nice.

That's where it all starts, 12 psi. From there you can be the master of your hydronic universe, or chase your tail depending on where the pump(s) go. And they should go after the scoop so that they add TO the system pressure.

Mod con piping is a variation, but follows the same principles.