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CBBP
Thud when running hot water

When running hot water or even when hot water is turned off there is a thud then a couple of seconds later another thud. This lasts for about 10-20 seconds....It sounds like it comes from the PVC pipes not the copper. Any ideas on what this is?

Re: Thud when running hot water

uhhhh...try letting your wife out of the basement?

I have the same problem........even after I let my wife outta the basement so I can;'t help ya...sorry:D

goldhiller
Re: Thud when running hot water

Wild guess from afar; the plastic pipe was fitted tightly thru a hole in a joist or stud somewhere and is rubbing on the wood when it expands and contracts.

(Let's hope this is not actually PVC if it's carrying hot water. CPVC is for hot water.)

Re: Thud when running hot water

How 'bout my hot water copper pipes? Every once in a while you turn it on and it sounds like its gonna blow up...major rumbling till I shut it off and try it again in a little bit or turn the water way low...I was thinking ..vent...but what would that have to do with a hot supply line?
Pipes are only five years old as is the faucet...or less. Its only that one kitchen faucet that does it and the island sink accross from it is fine although thats on a under the counter vent fwtw.

maybe I should start another thread...sorry for the hijack...cept I never heard of a pvc line doing that before...unless its a PEX line and even then...

goldhiller
Re: Thud when running hot water

Andy,

Has it done this since day-one or did the problem develop later down the trail?

(I thought you ran a bunch of PEX there. ??? Got a combo of PEX and copper, maybe?)

Are those copper pipes well secured to the joists or poorly fastened/supported?

Has anyone gone to watch the pipes when this happens....or are they completely hidden?

Rigid copper or flex?

Seasonal problem or year-round?

City water? Standing line pressure is?

Does it have any relationship to what other plumbing fixtures are being used at that time? (clothes- washer, dishwasher, toilet refilling, etc.)

Or perhaps it only does this when it is the sole fixture being used?

Rumbling is coming from the faucet itself...... or the pipes in the basement/walls.....or???

Have you tried temporarily swapping out the faucet for a different one?

Tank-type WH or on-demand? Does the WH have a swing-type check valve? Swing types can easily cause water hammer under certain circumstances.

Lived a winter some 20 years back on the second floor of an older house that had hot water heat. Older galvy pipes, tightly fitted thru the floor. (Hole more than big enough, but pipe was wedged against the side of the hole) Always knew when the boiler came on cause the pipe/floor would "pop"...loudly. Sometimes annoying when it did that, but when it was 20 below....it was always comforting to hear that sound.......even when it repeatedly woke me in the middle of the night.

Re: Thud when running hot water

Gold
Pipes are secure and they're rigid pipe..copper. I too thought maybe its when the washer was on upstairs but...nope. Doesn't happen often but often enough...I spose next time it happens I should crawl down in the crawl space and see if I can locate where the sound is the worst..Pipe is buried in the floor in insul 'tween the TJI's I framed four + years ago..
I'll probably keep ignoring it being it doesn't happen THAT often...just often enough for me to have talked about it here...lol..
I'm afraid to bring it to BT cause it'd prolly turn political...lol.
Started happening about six months ago.
I don't know why I keep thinking "vent" cause its the copper I hear I think...and its more than hear...I can friggin' feeland hear it upstairs even...
I should probably ask my plumber that put it in,,$$$$,,ugh,,,forget it,,,lol.

edit: Ya know..I seem to remember seeing a small copper cylinder 'bout the size of a tube of toothpaste in the plumbing dept that gets soldered in line...and I "think" it may be for this issue...I never even really even picked the thing up to read the package...maybe its for heat lines...its just some wierd thing that was in the back of my head with other useless information...or maybe it was in a dream...lol...I'll have to look next time I'm at HD.

Re: Thud when running hot water

Gold
Funny thing..I was thinking about our last post in this thread when my sink started blasting again today...I ran upstairs to see if the washer was on and voila'...it was on...cept it was on a spin cycle.
I ran back down to the sink and opened the cabinet doors below for a better listen underneath but that didn't help.

I for no good reason tried the hot water valve under there and it was down really low so I opened it up almost all the way...and the bangin' stopped. I had the valve turned down too low...lol.
Course it had to be sumpin' as simple as that. Valve was screemin' to be opened more...:rolleyes:

canuk
Re: Thud when running hot water

Ah yes ... the old valve wasn't open enough trick.:D

Don't you love it when it's a simple thing ?:)

Re: Thud when running hot water
canuk wrote:

Ah yes ... the old valve wasn't open enough trick.:D

Don't you love it when it's a simple thing ?:)

yeh, it just proves that more times than not the answers are usually right in front of your face.
We always complicate things :rolleyes:

canuk
Re: Thud when running hot water
andybuildz wrote:

yeh, it just proves that more times than not the answers are usually right in front of your face.
We always complicate things :rolleyes:

I hear ya... the K.I.S.S rule.;)

goldhiller
Re: Thud when running hot water

Andy,

Glad to hear that got resolved so easily. I suspect that the pipes themselves were fluttering and that's what you heard. Can't say for sure from here, but if there's a swing/flapper type valve at the WH......it can cause that under certain pressure/flow conditions. The valve itself will then/can...... rapidly flutter open,shut,open,shut....which will in turn cause the pipes to vibrate.

Or.....the vibration may have been generated right at the stop-valve in your case.

Can't help but think that the copper dealie you saw at the store was a hammer-arrestor. Spring-loaded likely.

You say you want this to turn political? ;) Be patient cause I'll have to work on that. Doesn't come natural to me. :D

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