Can’t figure out the banging noise in the radiator

csouza123

young plumber in Massachusetts, I got a call to fix a banging noise on the second floor of this massive Victorian style house in Lowell.

12 section boiler 450,000BTU Weil McClain natural gas boiler

For some reason, This is radiator is one of maybe 3 in the house that is piped with a feed and return (2 pipe) system where the others are just a 1 pipe system

The vent on the radiator is connected via a brass coupling where I think that it may have to be a horizontal vent..

The main steam supply in the basement doesn’t have any main steam vent

Boiler hasn’t been serviced in 5 years

any help is appreciated

My plan was to service the boiler, remove the radiator, clean it, pitch it more and hope for the best

Jamie Hall

The valves on that radiator suggest to me that this may have been piped as a two pipe air vent radiaator. One pipe generally led to a steam main. The other to another pipe which also had steam in it, but was intended to carry condensate back to the boiller as well. A return, if yu will, but not a dry return as would be found in later systems.

It works. Actually, in many ways like a one pipe system. However, pipe pitch — not so much radiator pitch — is essential to make sure that condensate can, indeed drain.

So that is where I would start looking. How does condensate drain? Are the pipes all pitched to allow it to drain freely?

Also make sure both valves are wide open…

bburd

There is almost certainly no point in taking out and cleaning the radiator. This is a pipe pitch problem. Condensate is pooling somewhere. Get rid of the pool and you will get rid of the hammer.

On the plus side, it looks like whoever installed that boiler actually read the instructions and piped it properly.

mattmia2

https://forum.heatinghelp.com/discussion/comment/1872139#Comment_1872139

well almost. the mains should come in to the header individually.

making sure the valves are both all the way open is my first suggestion

that coupler is because they couldn't turn the vent past the top

Big Ed_4

The trap may be plugged..

mattmia2

btw that is a very early style of radiator so that is likely a very old system that might predate thermostatic air vents

ethicalpaul

If the radiator is anywhere near level (and even if it's not), that's not your problem.

I agree with @bburd there is likely a pipe pitch problem in the short horizontal section in the floor.

You can try to lift the radiator on both sides (I see you already have it shimmed on one side) in an effort to correct what is likely a sag in the supply pipe.