[quote="SMITTY"]??? That valve in the picture is for cold well water -- it keeps the water from being forced out of the pressure tank & back down into the well. I'm trying to figure out what that was doing on your boiler!
If you can hear water flow in the pipes when the circulator kicks on, that means there is air trapped in them that needs to be flushed out.[quote]
I have been told that the person who originally installed this unit in the home is not out of business. Perhaps that's why it was on there, he may not know what he was doing. I guess that fits since I am not a master plumber myself.