In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Vacuum air vents on one-pipe systems
I don't understand why there aren't any manufactures who make air-vents for one-pipe systems that check the air. I am trying to understand what benefit there is to allowing the atmosphere back into the system after the radiators have condensed and so far I see none. I am not interested in creating an air-line or Paul system with forced vacuum. I am only interested in having the air exit and not return. Can someone please inform me why this is?
Detroit, Michigan (Dunham 2-pipe vacuum)