One loud thump

Elena08904

Hello,
My steam system is running well - thanks to hiring contractors from this forum to install and maintain it. However, recently we have been getting one loud thump from our kitchen radiator. I'm not sure if it is really from this radiator or we are just hearing it here because it may be the closest to the furnace. It isn't a regular knock but a thump. (It makes my dogs go crazy.) We aren't experiencing any knocking here or in other rooms.
Any thoughts?
In advance, thank you.
Elena

Hap_Hazzard

Is it happening once per cycle, and, if so, at what point during the cycle? Is the radiator in question hot when this occurs, or does it get hot afterwards?

Elena08904

Thanks, Hap_Hazzard. I don't know the answers but I will pay attention next time it happens.

Elena08904

I've heard it twice in the last 90 minutes. Both times the radiator was just a bit warm. I think the first time was after the cycle. The 2nd time was at the start of a cycle, I think.

SlamDunk

These may help. There are more in this sites' library


https://heatinghelp.com/systems-help-center/water-hammer-in-steam-heating-systems/

https://heatinghelp.com/systems-help-center/discovering-water-hammer/

Hap_Hazzard

Check and see if the supply pipe is binding in the floorboard. You can try grabbing the radiator and rocking it gently back and forth. If that doesn't do anything, you can try lifting it with a crowbar and a woodblock. Use the woodblock as a fulcrum and to protect the flooring.

ethicalpaul

I have one of these right now and I'm pretty sure it's due to my main pipe expanding (or contracting) and getting hung up on a hanger.

I have to re-do the hanger with slidy milk jug material

Fred

It could also be the radiator expanding and contracting and the feet catching the floor before it pops loose. Try putting a strip of a plastic milk jug under each radiator foot and see if that stops it.

Elena08904

what an interesting solution. Plastic milk jug. Okay
Thank you.