Toilet Water Hammering??

I'm a new homeowner in a 1-1/2 yr old townhouse. My wife and I just discovered a plumbing issue. After she had flushed the toilet in our upstairs bathroom, a very loud "jackhammering" sound occurred (sounded like it was coming from behind the drywall). The only way it would stop is if I shut off the water valve underneath the toilet tank or if I lifted the floatball inside the tank to stop the water from filling the tank. No other toilets or faucets in the house makes this sound. Is this what is called water hammering? If not, what could it be? Is this something that a novice could repair or is this whre I need to call the pros? Thanks for any help/input.

A water hammer occurs when you stop the flow fast, it doesn't occur while it is flowing. You could have some debris in the toilet fill valve that is causing the flow to vary. Cleaning the seal in the fill valve may help. There are probably other things as well. My unprofessional opinion.

Same thing happened to me.

When I would flush the toliet, the water would start to flow and then........ wham, wham, wham, wham, shutter,shutter, shutter........ I would quickly reach down and change the volume or amount of water coming into the tank. Strange as it seems, I would turn the flow "up" to get more water coming into the tank and the noise and banging would stop.

I can still make it wham and shutter if I go back to the lower water input, but of course, I don't want that...........
Tom

Jadnashua, Snowman, thanks for your input. As it turns out, I was about to take a look at the fill valve and clean/replace as needed, but first I turned the water back on to see if the "jackhammering" still occurred - it did until I opened the valve more and more. It eventually stopped, just like what happened to Snowman. If I close the valve a little for less water intake, the "jackhammering" sounds reoccur. So now, I just make sure that the valve is open all the way. Don't know why this is, but I can live with it. Thanks!

Good job on your detective work!

What happened was this: on the business end of the stem in your shut off valve is a little rubber washer, that actually stops the water flow when it is pressed fully against the inner seat. When fully opened, it just stays out of the way and minds its own business! When partly closed, 2 things happens. Water is still trying to rush into the toilet, but due to the smaller opening thru the valve, it moves faster. The little washer is loose enough that the increased water velocity can make it start to vibrate. This vibration in imparted to the water flow stream, and thus to the pipes themselves. Anyplace a pipe has some loose play, it will move and "hammer" the adjacent wood framing. I think that is more than "2 things" but I hope it helps!

Thanks Jimbo,
YOU win the prize!!! I always like to know WHY things happen the way they do...... You've given me (us) an answer that makes sense.
Now YOU need to write a book too....... Tom

change the ballcock

it is vibrating through the ballclck and whisteling

the easy thing to do is jsut buy a fluidmaster ballcock and change it out

Not on mine.........hammer and shutter seemed to come from water inlet pipe. When I reached down to increase the flow, the pipe and valve were in constant vibration.

I did replace ballcock with a Fluidmaster....... same hammer and shutter when water volume low. As I remember it, the Fluidmaster gave me less control over the problem. That was strange because I had installed, and was very pleased with Fluidmasters on my two other toilets. The ballcock would work quieter as tank filled, but I think that was a different issue. I believe it had something to do with the normal operation of the ballcock in the way it gradually shuts off water supply. Fluidmaster would not cause hammer when it shut off in a more positive manner. I think I liked the ballcock better because of the loud "sound" of rushing water through the line that I had with the Fluidmaster..... Sorry, if this doesn't make sense and if I seem to be contradicting myself.

It has been a couple of years, I can't remember all the details.
Tom

change the inlet valve

it sounds like tha washer in teh supply line stop is chattering.
try changeing the stop.


a question for you,,, how did you get your picture on bext to your name.??

I have been trying to upload my own picture for a while but to no avail....

what is the secret to doing this??

Hi Mark.......... guess what: You've got mail!