I’m having a water hammer problem in a ranch house that I need to get rid of 9the hammer, not the house). There is a full bath and washer hookup in the basement. The hammering ocurs mostly and most severly when the toilets (3 of them) finish refilling. The washer hot and cold lines have air cushions on them and those are the only ones I know of. The cushion pipes are about 12″ long and are the same diameter as the water lines. I’m going to try to drain the water lines to refil the pipes with air. My questions are, sholud these be sufficient to serve the whole house. I think I know the answer 🙁 . If the anser is no, then where else sholud they be? Are cushions necessary at every fixture? Would putting them on the main H/C lines that go upstairs be enough? Do they need to be vertical or is horizontal ok? Think I know the anser to that one too.
George
Replies
Just to be clear Water Hammer is bang, rattle, rattle caused when valve shuts off QUICKELY.
In general you only see this with toilet valves like the Fluidmaster and washer solenoid vavles.
Also with the new 2 handle cartridge vavles you can sometimes force them to do that, but typically not a problem.
A noise while water is running is a completely different problem. I have a fluid master that just started doing that. Sounds like a fog horn.
Surge or hammer arrestors are best located as close to the valve in question. You need something to absorb the surge of water that is being shut off by the vavle. An absorber on the other end of the line has limited affect.
Also it helps to have the pipes securely fastened.
The air chamber will absorbe water and soon (couple of weeks to a few months) and become useless.
There are several styles of sealed units. Some are a small chamber with a sealed piston. Others are a small tank with a bladder.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
sometimes there is an air bubble trapped in the line. I have eliminated that by shuting off the main line, opening every outlet in the house, set dishwasher and washing machine to 'start' so water will be pumped in immediately, and opening the main up about halfway until there is a steady stream at every outlet. this may flush the bubble out. not a guarantee but has worked on occassion
Orbs
A buble in the line will be quickly flushed out as you use water.What you are doing is completely drain the system including the water that is in the air chambers.Then when you turn the water back air is trapped in the air chambers and it acts as shock absorber untill the air is absorbed again..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Either the toilet valves are really cheap ones or you have some loose pipes. I'm betting on the loose pipes.
To add to what others have posted.
A whole house hammer arrestor will not work, the arrestor has to be at the end of the run where the surge is taking place.
If the problem is at a toilet, is usually from a loose pipe in the wall, one of the cheapest fixes is to use an angle stop with a built in hammer arrestor.
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“If Fred Thompson runs... then I think that makes it easier for me to not run.” Newt Gingrich
The hammering occurs when the toilet valve shuts off. It's a fluidmaster type valve that doesn't shut off gradually but sort of snaps shut as it reaches it's limit. Guess I'll try replacing the valve. Are there toilet valves that shut the water of gradually?
George
The float is sticking, is why it's shutting fast.
You can try some white lithium grease on the shaft that the float rides on.
“If Fred Thompson runs... then I think that makes it easier for me to not run.” Newt Gingrich
I would add the hammer arestor.That is the design of the fluidmaster and I think the other similar one (Corky?).It designed like that to have positive shutoff and hsyteris between on and off. Thus if you flapper is leaking it will draw down and 1" or two and then open for a few seconds. This "phantom" flush is a warning that the flush valve is leaking.First OEM units don' always shut off, stick, leak, corrode and just a pain.And if you get a small leak in the flush valve the fill valve will open just enough to keep the tank full and you never know it until you get a $500 water bill.Spend $10-20 and add on a sealed surge arrestor..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I've never had trouble with the Fluidmasters. Like I said, you probably have loose pipes.
If your view never changes you're following the wrong leader
GP,
Look at all the great advice you can get on this forum!!
You might be able to throttle the the angle stops at the toilets and eliminate this problem. It seems odd that you have this problem w all three toilets, and that you don't have some one off euro toilet that is the only one in country.
H
if area w high water pressure, may need to add water pressure regulator to drop feed pressure down to where it doesn't mess w appliances
Thought I'd provide a late follow-up. I was at the house this weekend and have gotten rid of the water hammer. I had to add lines for an outdoor shower a while ago and at that time put a ball valve on the main line. I cranked that down to about 3/4 flow. That helped somewhat but the hammer was still there. I then drained the whole house and refilled the lines - water hammer completely gone. Now I'll see how long it takes for the water hammer to return when air in the reserve pipes (or whatever you call them) gets absorbed.
George
So now you know how to stop the hammer, but you still don't know the cause for your house:
After draining the entire house piping and closing the ball valve slightly the hammer disappeared. Problem cured but you changed 2 variables.
Just for fun, reopen the ball valve to full "on". Flush a toilet or two.
Hammer return? - yes? it is pressure related.
No hammer return? - your air trap pipes were waterlogged - and now you know the cure.
Next time the hammer returns I would go exploring and try to find any loose pipes like DanH suggested. May or may not be easily accessed and anchored.
Jim
Never underestimate the value of a sharp pencil or good light.
Not exactly. I closed the valve some and tested the water, the hammer was still there, though slightly less loud. Then I drained the house and the hammer was gone so I'm pretty sure it was filled air chambers. I would like to check for loose pipes but they aren't really accessible.
George