On the second floor of my house (based in the US), all of my baseboard radiators make loud banging/knocking/hammering noises. This has been going on for years. My plumber tells me it may be the copper pipes rubbing against the wood (wherever the pipes travel behind the wall). The heating system is probably around 15 years old (gas furnace in basement for hot water).

I also read that bleeding the radiators may alleviate this issue, but I haven't looked for the valves yet (if they even exist). Somehow my plumber doesn't think it's caused by air in the system though.

Question for you experts: What are the next steps you would recommend I take, short of having the plumber open my walls. What are some of the low hanging fruits that I can perhaps try myself?

Thank you!

 

Thread moved to the boiler forum.

 

C,
You are using baseboard and rads in the same sentence but they are different types of heat emitters.

To start with pics of the system and emitters would be very helpful to identify what you actually have if possible.

As far as actual banging of pipes go, rubbing or expansion of copper pipes when heated when they are in an opening that is too small to allow for the copper to expand generally only lasts the first few minutes or less when the heat first comes on and it could not be mistaken for banging.

If things are that loud my guess is there might be something else going on.

Temp and pressure readings would also help.

 

This is a hot-water boiler, right? Does the banging mainly occur at the beginning of a heat call?

 

Thank you both for your responses. I will take pictures shortly.

The banging is only occuring during a heat call, yes. And then it often goes bang-bang-bang in short order until it settles a bit and the banging intervals stretch (but the banging never fully stops, the intervals just get longer). Then during the next heat call, it's the same thing.

So in the basement, there's a Weil-McLain gas furnace. On the side of it is a red pump that I think performs the hot water circulation to the radiators upstairs, via copper pipes.

Would 'bleeding' the baseboard radiators help in any way? I don't even know if they have any valves, bbu wanted to ask here first before I do something stupid.

 

If you are getting good heat I would try bleeding anything yet. If there was air in the system you would hear gurgling or sounds of water rushing through your baseboards.

If everything Is quiet except for the banging I doubt that it's air but pics might show something.

 

A little helpful info............ How-to-insert-pictures