Beating my brains out!!!!!

[dcsommer]

I need some troubleshooting help, big time.

When in my downstairs master bathroom that is adjacent to the water heater in the garage, I get an in-the-wall dripping sound ONLY when running the hot water in the sinks. I removed (destroyed) the drywall from the garage wall and cieling, and have only found a PVC vent pipe that rises between two studs until it makes an 90 degree for about 2 feet into the garage (parallel with cieling), then makes another 90 degree and heads up through the second floor tongue-in-groove OSB deck.

I believe that the PVC is some sort of vent pipe, and that when I grab it at the elbow the dripping noise ends. Is this posssible? The pipe and elbow joints move pretty easily when grabbed, and I am in North Carolina where it recently became a little chilly. It is a tract house built during the early 90's, and I am not completely confident to rule anything out.

The plumbing in my house is poly with copper elbows if that matters, at least what I can see of it. I know the issues with poly and am hoping it is not that. I don't believe it should be with the copper fittings.

Please let me know if you need more info. I am hoping to solve this issue before demolition heads toward interior walls. I tell my wife I am going to tear our house down looking for a drip. The crown royal highballs it is forcing me to drink does not make the situation better!!!!!

Thanks in advance,
Dave

 

[Terry]

If you don't see any signs of water, it may be that the pipe gets longer when you run hot water through it.
Then as it cools, it shortens back up again.

Most of the time, it's more of a knocking or clicking sound.

 

[Sponsor]

 

[steelydanfan]

I agree with Terry. This sure sounds like expansion/contraction of the PVC pipe as it heats/cools, as the pipe passes tightly through a wood member. This is especially prevalent in cold weather and when the pipes are located adjacent to exterior walls.

 

[Master Plumber Mark]

knocking and clicking soun d

you will probably have to knotch out the wood

at and around the botom of the stack to rid yourself

of this annoying sound....


I have sprayed the joysts with WD40 before jsut to appease

a customer..... that seems to work for a while.....

 

[Randyj]

I've got the same problem under my bathroom sink where someone ran CPVC thru the floor then pulled the pipe over to force it to the sink...every time the pipe warms up it sounds like dripping water on the floor.

 

[dcsommer]

You guys are good. Worked to perfection. I was telling the story at the office yesterday and someone recommended replacing the WD-40 with baby powder for longer lasting solution. Anyone ever heard of that?

 

[Cass]

Try it, it can't hurt, then let us know.

 

[Randyj]

Baby powder has talc/talcum powder which consist of sliding plates of material much like graphite... graphite would work good too, repel water and be a super good lubricant....but it's nasty as hell.

 

[Master Plumber Mark]

baby powder

baby powder ????


I use it in my shorts once in a while.....

its great when things have been rubbing
against each other and get raw and itrritated.....


But, I dont know if it will work on those kind of pipes....

 

[Randyj]

Mark... try Udder Balm... that's the greatest stuff in the world for any kind of chaffing and great for sun burn too as well as raw hands from dishwashing, psoriasis...etc. Most farm stores sell it.