New Return Pipe Noise During Renovation

JodiMe

Hi all -

Can a leak in a return pipe cause water hammer? Noticed a slight one tonight in a connection.

We have been troubleshooting water hammer issues this week as our basement is under construction and there’s a lot of moving parts down there. Pipes are pitched ok, boiler has been skimmed, and no boiler settings or anything else with the radiators have changed.

Thanks,

jodi

EBEBRATT-Ed

The leak wouldn't cause the hammer but it is possible the hammer caused the leak if it went on long enough.

If you have water hammer you will know it you can't mistake that noise.

If you re getting "ticking" that is probably expansion and contraction. Check the piping in that area for pitch and also check to see if it is rubbing against framing members etc. The pipe should be hung so it is free to move.

JodiMe

oh I know water hammer! This isn’t as hard as they by any means, and now that I’m listening with that in my head, it’s likely what it is. We will have our contractor repair the leak today and then take a look at where the pipes touch the wall and adjust if needed. Will keep you updated - thanks!

dabrakeman

Leaks in return pipes usually come from standing water in that return pipe. Might there have been a sag that you are now correcting? When you say return pipe is this the extension of the main back to the boiler (above waterline)? Do you have a one pipe or two pipe system?

JodiMe

we have a two pipe system. There are definitely issues with pipe pitch - which is likely what caused two leaks a couple weeks ago (that have since been fixed). I think the current leak isn’t from standing water (it’s in a vertical pipe) and just something loosening from the construction and us re-pitching.

JodiMe

Here’s a link to a video of the sound that the pipes are making, for reference. When close it does sound like a slight hammer in the return but it’s rhythmic like there’s expansion. Very confusing.

https://photos.app.goo.gl/o5ieq48ywtXft1Jk7