Copper Pipe making noise in the wall

[rentonhighlands]

Hello:
I have a copper pipe making a clicking banging sound in the wall when the hot water from my kitchen (up stairs) is turned off after use. The clicking sound continues for about 30-45 minutes. I am wondering if this is water hammer? And or can be a loose pipe strap in the wall.

I am reading on the web and I find this set of directions. Would this be a good thing to try?

Shut off your home’s main water supply valve.
Open the highest faucet inside your house.
Find the lowest faucet on the property — it’s usually on the first floor somewhere outside or in the basement — and turn it on to completely drain all water from the pipes.
As the water drains from the pipes, air automatically replaces it.
The moment the water is completely drained from the piping, turn off the lowest faucet and reopen the main valve.
Air pushes out of the horizontal and open vertical water lines, sputtering as it exits the faucets inside. However, air remains in the air chambers, eliminating water hammer.

 

[rlitman]

Copper pipe expands and contracts with changes in temperature. This sort of sound is commonly associated with baseboard radiators, where the pipe is caught in a hole through wood. It is the sound of it rubbing as it moves.

The solution would be to enlarge the hole, so that the pipe doesn't rub. But you could also try to lubricate it with some grease. I've had that work where baseboard pipes pass through walls.

 

[The Cobbler]

the noise is probably the copper expanding & contracting wit hthe heat/ cool down
as said, it's rubbing somewhere making the creaking

 

[Anthropic]

Mine does the same thing!

 

[glentre]

Could be water hammer making the banging noise when the hot water is turned off. Try turning the hot off slowly to see if the noise diminishes or stops. Hammer can also be caused by a loose faucet washer. Hammer noise can come from either the hot or cold pipes. Has the banging been going on for a long time or just starting? Just starting might indicate a washer beginning to loosen. Also, very high water pressure can cause shut-off hammer so another solution might be to reduce the pressure if your system allows you to do it. Close your main shutoff a little or dial back your pressure reducing valve if you have one. Well systems will always have a pressure valve.

Unless you have a newer home or a home in an area where water hammer chambers are the code, it is unlikely the web instructions will help, although worth a try because you probably don't have the chambers in your system. These would be capped off vertical pipe extensions in the wall and above the sink faucet supply which fill with air as the system is drained and refilled. The air cushions the abrupt shutting off of the water and eliminates the hammer sound.

The clicking sound could be caused by expansion and contraction of the pipe as it goes from cold to hot and back to cold and, if this is the case, would not be related to your water hammer problem. The noise would be more prevalent when turning on the hot water because the pipe would expand quickly with the introduction of hot water from your heater. Pipe straps anchored tight to the pipe could cause that clicking noise as the pipe expands and contracts but 30-45 minutes sounds like a bit long for the clicking noise to continue. It might occur longer if the pipe is in a lightly insulated or uninsulated outside wall where the cavity is cold. In this case, the noise would last longer in the winter than in the summer. Your might also check the temperature set point of your water heater. Water that is too hot would cause more and quicker expansion of the pipe and more clicking noise.

Lacking more details, these are a few things to consider.

Glen

 

[rentonhighlands]

Hammer noise can come from either the hot or cold pipes. Has the banging been going on for a long time or just starting?
The banging has been going on for a long time.

It might occur longer if the pipe is in a lightly insulated or insulated outside wall where the cavity is cold.
This sentence describes the location of the noise. The wall is an inside wall but up to the outside wall of the house down stairs in the laundry room.

Your might also check the temperature set point of your water heater. Water that is too hot would cause more and quicker expansion of the pipe and more clicking noise.
I also found this on the web. What is the max set point I should set the water heater to?

 

[glentre]

Recommended temp is 120* but this depends. For households with elders or small children in danger of scalding, you might want to set it lower. If no kids and your heater is small and you run out of hot water, might want to set it higher.

Glen

 

[Outlander]

My house, built by my dad in 1949, has always done this in one spot. It is comforting

 

[dutchgray]

I doubt its water hammer if it goes on for 30 minutes or more, no way would you be able to put up with that, water hammer is usually pretty loud, so its probably thermal expansion and the pipe rubbing on some wood somewhere, find it and lag it with something that the pipe will slide in. We use Hair felt here, or traditionally lead on the joist cutouts where the pipes sit.

 

[flat350]

It's not water hammer,and don't bother messing with the water heater,all it is is the pipe expanding and contracting as it heat's and cools.Somewhere along it's run it's tight against a piece of the framing and the tick is from it rubbing there.The only way you'll find it is to examine it at very location that it passes through the structure near the location that it ticks at.

See my sig............................

 

[firebirdparts]

It's not water hammer. Please don't listen to anybody who thinks water hammer continues for 45 minutes with no flow.

 

[ford33]

Water hammer does not last for 30 minutes. It is likely the noise you hear is the pipe expanding when warm and then contracting when cooling. The pipe is rubbing against wood or something as it passes through the floor, wall support or ceiling. You need to open the wall and inspect the pipe installation and eliminate the contact point with the pipe. Enlarge the holes or cushion the pipe around the holes.

Get a stethoscope or flexible hose and listen to the wall. Sometimes you will need to drill a hole in the wall near the noise and place the scope into the wall. You can use the stethoscope to locate the noise easily.

 

[wssix99]

I had this exact issue on a new run of pipe in a new house. The issue was that the pipes popped their brackets and were moving.

You'll need to open the wall and either fix the rub or clamp the pipe down so it moves less as it expands during heat-up.

 

[Farrier]

It's not water hammer.

If you have a traditional tanked water heater, I bet you have calcium/deposits built up in the tank, causing it to pop whenever there is a demand for hot water. Drain the tank. I bet you get some gooey white stuff that dribbles out.

 

[rentonhighlands]

Thank you for all this information
I fount the water pipe with the water valve exiting from the wall going to the cloths washer is loose. I can push the pipe in and out as it slides though the wall. However this is not where the noise is coming from however it is most likely tided to this pipe being loose.

The noise is further up the wall and toward the outside of the wall.

Can I do this or would this be a bad idea to try?
Drill a small hole in the wall and spray some spray foam in the wall? I am thinking when it expands it will wrap around the pipe and make the pipe tight in the wall.

 

[rlitman]

Making the pipe tighter probably won't stop the noise. It could possibly make it worse.

 

[rentonhighlands]

Ok
It has been suggested I open the wall. I am finding the solution to be, I will need to wrap the pipe with some styrofoam type material the black pipe wrap stuff to make the pipe stop banging on the wall stud?

Or if a strap is loose put a new ******** the pipe. This would make the pipe tight against the wall stud. Or if the pipe is loose in the whole going through the stud what do I stuff in the hole?

 

[LS6 Tommy]

It's not water hammer. Please don't listen to anybody who thinks water hammer continues for 45 minutes with no flow.

True. It's the copper contracting and rubbing on something as it cools down.

Tommy

 

[rlitman]

The pipe needs to be loose in any places where it goes through a stud. The copper rubbing and sticking against the wood is what makes the banging.

Either the copper should be so loose that it doesn't rub, or you lubricate the sticky spot with something. I had suggested grease (not a great suggestion, but in an otherwise unreachable space, spray lithium grease worked for me), others have suggested felt (this is better, if you can get it in there).

 

[Bluevista]

The drain and vent lines can click and pop long after running the hot water from expansion and contraction too.
I find that to be the case more than water lines when I'm chasing those noises, especially PVC, but they both do it if they're not run correctly.

 

[redmondjp]

They make special clips and plastic grommets for copper pipe that hold it in place but allow it to move slightly as it expands and contracts.

 

[kbs2244]

I was going to join the pressure pipe being too tight in a hole or clamp.
Until the PVC drain/vent idea was brought up.

Is this a new problem?
What, if anything, has been done to create this problem.

 

[ford33]

The pipe needs to expand and contract in the wall. The solution is not to secure the pipe tightly but to quiet the pipe where it contacts a wood wall or mounting bracket. Look for contact points and then apply a nylon or felt support or enlarge the hole in the wood so the pipe can move easily in the hole.

 

[wssix99]

The pipe needs to expand and contract in the wall. The solution is not to secure the pipe tightly but to quiet the pipe where it contacts a wood wall or mounting bracket.

You are assuming that the pipe is properly secured in the wall to begin with, right? (That may not be the case.)

Can I do this or would this be a bad idea to try?
Drill a small hole in the wall and spray some spray foam in the wall? I am thinking when it expands it will wrap around the pipe and make the pipe tight in the wall.

I would say your chances of making a bad situation worse or creating a new bad situation are much higher than doing a proper fix. If you are going to live with this for a long time, there's no way to get around opening up the wall...

 

[AMCguy]

Shouldn't knowing exactly what is causing the sound and that it's simply a characteristic of copper pipe under those circumstances comfort you into taking no action at all?

 

[Lelandwelds]

Have kids or keep the TV turned up. It will be too busy or too loud to notice the little things.

 

[Bruce Amacker]

I had the same problem and sprayed a little bit of spray grease where it went through the wall. It's been 2-3 years and silent since.