Pulsating pipes

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dorlando

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Hello,

Two or three times a week over the last few weeks the shower pipes, I assume the pipes, will pulsate while the shower is running. It is strong and loud. We also have a problem with the toilet in the same shower and it is making odd noises when not in use, can't say it is a hammer but not water girgling. It can be loud also.

Any ideas where I should start? I did have to repair a pipe in the attic a few months ago, the pipe does lead to that bathroom, but all I did was replace a tee. The shut off valve is also on the outside of the bathroom wall and it might have a small leak that I need to check out. Not sure if this can cause the pulsating.

Should I check for something in the shower valve? Pressure? Thank you
 
What other information would be helpful? There is no pressure relief valve other than a valve on top of the water heater.
 
type of shower valve (pressure balancing?) static water pressure, piping material, strapping spacing, nature of contact of pipes with building structure.
If it is pressure balancing shower valve, replace the cartridge might be easiest.

Puslating pipes does not describe anything physical. Do the pipes bang, move?
Did this just start out of nowhere?
 
That all makes sense. This just started a few weeks ago, the shower has been in place for almost 3 years. I don't recall the type of shower valve, I will need to check but it wasn't a cheapo one. It was a name brand but I know that doesn't always mean anything. I will be checking the water pressure from the hose bibb tonight. The pipes are CPVC, not sure about the strapping spacing. I really can't say if the pipes are moving or banging but my wife says it sounds like a water hammer sounds. It is a thump, thump, thump, repeatedly for up to 10 seconds and then it just stops on its own. It happens when the water is running and happens ever 2-3 days. I don't think I have had it happen to me so don't know if that may be because my wife has the temperature different than I do. The other day I did think the pressure was a little low for me but then it got better later in the shower.
 
You mentioned, "shut off valve is also on the outside of the bathroom wall and it might have a small leak that I need to check out."

Does that shut off control the water to your shower?
Are you talking about a stem packing leak?
What type of valve?
Is this the shut off valve you used when replacing that tee?
Globe valves with washers are known to cause noises when the washer get loose.
 
Thanks for the response. The valve is on the main line coming into the house and going to the water heater. It's just a valve that has a twist handle on top to turn the water off that is coming into the house from the street. I uploaded a picture of what mine looks like, this isn't my valve but this is the type. When I looked this morning there was a little water sitting in the middle of the handle. Whether it was from the overnight dew or not I am not sure but I will be looking at it more closely. If there is a leak, maybe due to a washer, is it possible that is causing the problems? I don't think the shower is fed directly from that valve as it goes to the water heater first.

That is not the valve that I had to replace. What I replaced was a tee in the attic that I stepped on. The tee was connected to the hot water pipe that is leading to the shower. I replaced the tee exactly how it was.

How would I tell if I have a pressure balancing valve in the event that is causing the issue?
 

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A couple of questions.
What would be the best way to fix the ball valve leak?
Can that leak be causing the issue with the shower line thumping.
 
I am not familiar with those $1.50 PVC ball valves from China.
Don't know if packing is replaceable.???

A ball valve would not be the cause of the thumping.

If it was a globe valve , it could.
 
ok. How about the cartridge in the shower valve? Should I start there? I can send a picture of the valve tonight when I get home.
 
@breplum Here is a picture of the shower valve. Is there something I should replace?

water pressure at main valve coming into the house is 60psi. There also doesn’t appear to be a leak at that main valve. My wife said when the thumping happens the water is actually sputtering during that time as if maybe air is in the pipe or there is a blockage. That sputtering appears to be causing the pipes to shake
 

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So this morning the pipes were pulsating with no water running in the house. About 20 minutes after taking a shower the pipes pulsating for about five seconds. I was not able to tell where it was coming from. What would make that happen with no water running?
 
I have a Grundfos recirculating pump that will pulsate through my pipes several times a day, pushing hot water to my longest legs of plumbing. Have you checked for this?
 
It could be a leaking toilet flush valve flapper.
When the tank partially refills, the fill valve could be getting noisy.
Just an idea.
 
I have seen similar intermittent noise based on Mr. Handy’s conjecture above. Here is the set-up:
The shower is running. The toilet float valve opens, due to a flush or a partial refill because of a leaking flush valve. The type of float valve does not matter much, but pilot types, such as Fluidmasters, seem to be more common. (Full open or shut, no “tiny trickle flow”) The pulsation originates from a supply stop on the toilet or a globe stop on the hot or cold shower supply. As the Bibb washer ages and shrinks it gets loose and can wobble in a nutation motion that is flow dependent for frequency. The frequency may find a pipe length harmonic that amplifies the audible noise. This may be confirmed further by a fade in-fade out effect caused by the change in frequency caused by change in flow across the offending stop valve. The quick fix would be to simply change out the toilet supply stop with a 1/4 turn type.
Another more rare cause is a loose in-body shower diverter of a piece of debris hung on such a diverter or in a twin ell diverter.
 
Thanks. I have replaced the seal cap in the fill valve as a starting point. If that doesn’t fix it what toilet part would you suggest I replace next?
 
Change the flapper on the toilet that makes noise.
So it will stop leaking, which might have been causing the noise from partial refilling while not being used.
Change the supply valve on that toilet.
Or open it all the way, if it is partially closed.
Repair or replace the isolation valve that sends cold water to that part of the house, if there is one.
Or repair the shutoffs at the water meter.
Change the shower cartridge.
Start with the easy stuff first.
 
Thanks. I did replace the seal cap and still have the problem. I will work on other things. What happens is water sputters from the fill tube line into the overflow pipe and makes a sputtering noise. It isn’t a constant stream of water, it sputters in but it does it randomly, meaning not when toilet is flushed
 

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