Solving Water Hammer

[Scouzer]

I think it's water hammer anyway. When I flush the toilet on the second floor of my townhouse, the plumbing makes awful clunk clunk noises. It's fairly loud. It's not standard pipe noise I don't think. It sounds pretty nasty.

Is this just annoying or do I need to get this fixed? I doubt I could do this myself.

 

[TechBoyJK]

I think it's water hammer anyway. When I flush the toilet on the second floor of my townhouse, the plumbing makes awful clunk clunk noises. It's fairly loud. It's not standard pipe noise I don't think. It sounds pretty nasty.

Is this just annoying or do I need to get this fixed? I doubt I could do this myself.

could be a few things. google water hammer and you will be suprised as to how much there is on it. it's a fairly common problem. apparently, a fix is to cut off the water to the house, and open all the valves and let what water is in the pipes run out, then turn the water back on. has something to do with clearing out air in the pipes.

 

[Scouzer]

could be a few things. google water hammer and you will be suprised as to how much there is on it. it's a fairly common problem. apparently, a fix is to cut off the water to the house, and open all the valves and let what water is in the pipes run out, then turn the water back on. has something to do with clearing out air in the pipes.

Yeah I was looking at that. So to empty out the pipes to a toilet I'd just flush a few times after shutting the water off I guess?

I don't even know if I have a master house valve accessible by me. It may only be accessible by the city or my condo board.

 

[mshan]

Water hammer arrestor?

Lowes has some really cheap one (Sioux Chief Mini-Restor, I think); Watts 150a is a more heavy duty option.

You could try opening a water faucet in that bathroom temporarily when toilet is refilling and see if that helps.

Usually means there is a pipe that is not secured and there is rattling when pressure wave propagates through pipe. Think I also read it may mean there is an air pocket vacuum in line, thus recommendation of draining system and refilling.

I have same problem and bought some Watts 150a, but am still trying to figure if I can just go to Home Depot / Lowes and get proper adapters for screwing them into toilet line, or if I need a professional plumber to put in correct fitting using blow torch.

 

[Red Squirrel]

Yep get a water hammer arrestor, best bet, and easy to install. I'm not sure about a toilet, but I know the ones for my laundry were screw in, no soldering required. Just put teflon tape around the threads (optional, but I'm paranoid with this stuff) and screw it in. A toilet probably has the same threads for the screw on connector... maybe someone else can confirm.

If you have physical access to the pipes you could try to secure them better as well.

 

[Scouzer]

So the water hammer arrestor actually screws into the water INPUT line to the toilet? I was always under the impression the noise was caused by the water flushed down the toilet.

Not that I could tell either way, lol.

 

[MikeyIs4Dcats]

buy a water hammer arrestor

 

[Red Squirrel]

So the water hammer arrestor actually screws into the water INPUT line to the toilet? I was always under the impression the noise was caused by the water flushed down the toilet.

Not that I could tell either way, lol.

Actually do you think the sound is coming from the drain part? From what you describe it sounds like it's coming from the water supply being shut off fast by the toilet when it's done filling. A water hammer arrestor anywhere on that path will help, normally at the appliance itself. As a quick test just turn on the water at the sink and turn it off very fast, see if you hear the same sound.

 

[mshan]

Water hammer arrestor has a pocket of air in it that is supposed to blunt pressure wave propagating through pipes when flow of water stops abruptly.

That Mini-Restor has a tiny pocket of air that will eventually get absorbed over time. The Watts has a much larger pocket of air, and there is like a tire valve opening that you can use to add more air.

 

[iGas]

The noise is from a lose pipe and could also be from a trapped air bubble in the line prior to the toilet. Water hammer tend to be cause by fast closing valves such as clothe & dishwasher.

That said, you can try shutoff the water from the main and bleed the line at the lowest location with all valves in the house open. Or, attach a simple water hammer arrestor on the line near the noise to see if it fix the problem. Other wise try to locate the noise, and cut out the wall & strap the pipe down.

Good luck.

 

[iGas]

The Watts has a much larger pocket of air, and there is like a tire valve opening that you can use to add more air.

That sounded like you are describing an expansion tank, or pressure tank.

 

[bctbct]

That sounded like you are describing an expansion tank, or pressure tank.

I had this happen on a kitchen sink one time and found out it was because the shut off valve under the sink was not all the way open.

 

[WHAMPOM]

If it "hammers" when you flush, it may be due to the sewer system vent being pluged.

 

[iGas]

I had this happen on a kitchen sink one time and found out it was because the shut off valve under the sink was not all the way open.

A partially open valve could cause an air bubble to trap, thus creates noise as water passes by. Or, or lose valve seat that vibrates as water passes by (lose seat also wears the valve out quicker).

 

[iGas]

If it "hammers" when you flush, it may be due to the sewer system vent being pluged.

????

What drainage have to do with supply water?

 

[Rubycon]

Can you record the noise?
Water hammer occurs when the SUPPLY water valve is closed suddenly. On a sink or bath faucet you can control how fast you shut it off - so no water hammer. If you have one of those "stick shift" type knobs and slam it down you will probably have hammer.

Solenoid valves in dishwashers and washing machines definitely shut off very quickly - their smaller diameter prevents larger flows like you may have in a sink but they still cut off really fast so the chance of hammer is higher.

Also note that the higher your water pressure is overall the better the chance you will have water hammer.

Severe water hammer makes a ba-ba-ba-ba sound similar to the "bionic man" sound effect. If the pipes rattle like that it may be more than an annoyance it could lead to a failure. Again depends on how high your pressure is.

You probably should get your pressure checked. You can install an arrester or make one yourself. It's nothing more than a coil of tubing or a large dead end riser. The important thing is it stays filled with air as air is compressible and will help absorb the shock. If you make one it may be a good idea to sweat a shraeder fitting at the end so air can be added if it gets filled with water after a while like the old bladder-less style well water tanks.

 

[EricMartello]

When I eat burritos or kraut, the next day I usually have a monster shit and when I flush it I can actually hear it thud when it hits the bottom of the drain pipe from the upstairs toilet. I'm just worried that someday I may end up breaching the hull if you know what I mean.

 

[Rubycon]

When I eat burritos or kraut, the next day I usually have a monster shit and when I flush it I can actually hear it thud when it hits the bottom of the drain pipe from the upstairs toilet. I'm just worried that someday I may end up breaching the hull if you know what I mean.

D:

Get one of these.

http://www.youtube.com/watch?v=xXsvbpYRNvU

 

[iGas]

Can you record the noise?
Water hammer occurs when the SUPPLY water valve is closed suddenly. On a sink or bath faucet you can control how fast you shut it off - so no water hammer. If you have one of those "stick shift" type knobs and slam it down you will probably have hammer.

Solenoid valves in dishwashers and washing machines definitely shut off very quickly - their smaller diameter prevents larger flows like you may have in a sink but they still cut off really fast so the chance of hammer is higher.

Also note that the higher your water pressure is overall the better the chance you will have water hammer.

Severe water hammer makes a ba-ba-ba-ba sound similar to the "bionic man" sound effect. If the pipes rattle like that it may be more than an annoyance it could lead to a failure. Again depends on how high your pressure is.

You probably should get your pressure checked. You can install an arrester or make one yourself. It's nothing more than a coil of tubing or a large dead end riser. The important thing is it stays filled with air as air is compressible and will help absorb the shock. If you make one it may be a good idea to sweat a shraeder fitting at the end so air can be added if it gets filled with water after a while like the old bladder-less style well water tanks.

Higher pressure doesn't mean that you are more likely to have water hammer it just that the effect is exponentially greater as pressure climb.

ba-ba-ba-ba sound, is more likely that you have a lose/worn valve seat.

I haven't seen a coil that is use as a water hammer arrestor. A vertical dead end pipe as water hammer arrestor is no longer in use for more than 20 years because it will be water logged within days, as you must shutoff and bleed the air out every couple of days if it have bleed valves & shutoffs.

And I never have seen or heard of sweat shraeder fitting. I think you mean a 1/2" x 1/4" sweat FIP bushing that you can screw the shraeder valve into. (There are 1/8" shraeder but they are hard to come by)

 

[Rubycon]

Higher pressure doesn't mean that you are more likely to have water hammer it just that the effect is exponentially greater as pressure climb.

ba-ba-ba-ba sound, is more likely that you have a lose/worn valve seat.

I haven't seen a coil that is use as a water hammer arrestor. A vertical dead end pipe as water hammer arrestor is no longer in use for more than 20 years because it will be water logged within days, as you must shutoff and bleed the air out every couple of days if it have bleed valves & shutoffs.

And I never have seen or heard of sweat shraeder fitting. I think you mean a 1/2" x 1/4" sweat FIP bushing that you can screw the shraeder valve into. (There are 1/8" shraeder but they are hard to come by)

Increasing pressure increases the effect of the water hammer so yes if your incoming pressure is too high - say 80 psig then it can be turned down a LOT and the banging WILL be quieter.

Stubbed shraeders are common in the refrigeration biz. Drill a hole anywhere in a copper line and braze (silphos) it in! Of course these don't fit a tyre air chuck but chances are if someone knows what these are they have a gauge manifold and adapters.


EDIT:

Your first reply about tightening the pipe straps and installing something at the faucet is probably the easiest but I have to wonder how high the OP's pressure is.

 

[iGas]

Increasing pressure increases the effect of the water hammer so yes if your incoming pressure is too high - say 80 psig then it can be turned down a LOT and the banging WILL be quieter.

Stubbed shraeders are common in the refrigeration biz. Drill a hole anywhere in a copper line and braze (silphos) it in! Of course these don't fit a tyre air chuck but chances are if someone knows what these are they have a gauge manifold and adapters.


EDIT:

Your first reply about tightening the pipe straps and installing something at the faucet is probably the easiest but I have to wonder how high the OP's pressure is.

His question wasn't clear, therefore I suggested strap down the pipe if the noise came from that area, as it could be an over sweated fitting (over pregnant bead of solder) in the line that could cause a small air bubble to trap at the fitting.

 

[Red Squirrel]

Increasing pressure increases the effect of the water hammer so yes if your incoming pressure is too high - say 80 psig then it can be turned down a LOT and the banging WILL be quieter.

Stubbed shraeders are common in the refrigeration biz. Drill a hole anywhere in a copper line and braze (silphos) it in! Of course these don't fit a tyre air chuck but chances are if someone knows what these are they have a gauge manifold and adapters.


EDIT:

Your first reply about tightening the pipe straps and installing something at the faucet is probably the easiest but I have to wonder how high the OP's pressure is.

Actually that reminds me, at my parents house we had a water hammer issue, and it turned out we simply had WAY too much pressure. It was well over 100 PSI and think it's suppose to be like 60 or something.. I forget the exact numbers, but we were way up there. Strapping the pipes only worked temporarily, then they'd get loose again. The basement was not done then, so it was easier, but now that it's all dry walled it's more involved to do such a fix. It's funny since I tried to convince my parents to put drop ceiling but they did not want to... sure enough a few years later there was a water leak lol. Always go drop ceiling in a basement.

 

[Rubycon]

LOL 100 psi? Talk about pissy water.

 

[iGas]

Actually that reminds me, at my parents house we had a water hammer issue, and it turned out we simply had WAY too much pressure. It was well over 100 PSI and think it's suppose to be like 60 or something.. I forget the exact numbers, but we were way up there. Strapping the pipes only worked temporarily, then they'd get loose again. The basement was not done then, so it was easier, but now that it's all dry walled it's more involved to do such a fix. It's funny since I tried to convince my parents to put drop ceiling but they did not want to... sure enough a few years later there was a water leak lol. Always go drop ceiling in a basement.

Most cities water service rarely jump to 100 PSI & beyond except for the few times that they have to service the main pipe and use a booster pump on the bypass.

Most fixture valves & stop valve are rated for 90~100 PSI, and greater pressure than that, the bonnet gasket on the valve or the seats quickly fails.

Default manufacture PRV (Pressure Reducing Valve) pressure setting is around 70~75 PSI (PRV range can be 55~80 PSI).

Plumbing code indicates that residential max service pressure is 80 PSI.

It is possible that water hammer is the cause in the leak at your parents house, but it is more likely that the fitting are poorly soldered, damaged or manufacture defect pipe, or the area have hard/very soft water.

 

[Rubycon]

100 would do nice on an R/O unit though. Definitely no booster pump required.

I don't think toilet hardware (float shut off) will like that very much though. They just make them so cheap these days.