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Two pipe air vent system – banging in just one radiator
Hi – I love this site and have found it tons of help.
One radiator, 56” long, second floor, very slight pitch to return, with two-pipes with air vent. When the supply is CLOSED – no banging and some heat at the return side. With supply OPEN, lots of banging and heats like the dickens (207 degrees across the full radiator).
The supply and return pipes run about 5 feet horizontally between the first-floor ceiling and the second-floor floor. The return valve is open. The air vent is set at medium.
I’ve had this problem for a while, and cannot think of something that I changed to create it. Its only become an issue recently because the room is being used and needs some heat