Steam boiler making loud horn sound

tsgrau

I recently changed all of the vent valves on my steam radiators to a new valve from heat timer called very valve adjustable vent valve. I did this because the previous valves that I had were not adjustable and I was having trouble getting the heat balanced in my house. I thought that these new valves would help me to be able to have better control to get the heat to balance in every room. Since I've added these valves come up my boiler is making this weird new noise. It happens after the heating cycle and it sounds like a horn. I. Tried to attach a video with the sound but it won't accept my MP4 video.

It seems like it may be sucking air in? I have also noticed that this only lasts for maybe 10 minutes after the heating and occurs about 3 or 4 times.

I added a picture, and it sounds like the noise is coming from the black pipe that is pointing straight down out of the t-shaped brass fitting for the water refill loop.

Steamhead

That T-shaped device is a backflow preventer. If the boiler goes into vacuum after it shuts off, it's possible air can be sucked into the vent.

Regarding the uneven heat- do your steam mains have good vents on the ends?

EdTheHeaterMan

Did your boiler operate without the horn noise before you added the valves?  Is this a one pipe steam system? A picture of any radiator showing both ends at the bottom, to see the new valves you installed, will tell us that answer.

I can see that you have both boiler side supply openings connected to each other and you also have the main riser connected to a tee where the bull or branch of the tee is the end of the header and one of the thru tappings is connected to the equalizer and the other is connected to the system riser. Not the best design but if it worked without noise and banging before the new valves, then that piping design is not your problem. (if it ain't broken don’t fix it). It has something to do with the new valves.

I kind of remember that a partially closed valve like the one you have described might not be a good idea on a one pipe steam system.  You want that valve either open or closed.  Never partially open. 

Are your heat timer valves actually adjustable air vents that are connected to the side of the radiator opposite the inlet valve?

To show a video you need to put it on the web with TikTok, Facebook, youtube or something else and just post the link to the video. This platform does not support MP3 files