Got a call from a client, they’re having a problem with banging pipes in their entry-level tract house. I have not been to the house yet, but I asked a few questions and here’s the clues so far: Seems to be loudest in the first floor laundy room, which is also where the water heater is. Watering the back yard seems to cause it a lot. Sometimes flushing a ‘mode does too, as does the washing machine. They don’t think the dishwasher causes the noise. Houise is two story, concrete slab on grade, wood studs, hard water, built in 2000. Any ideas? What should I look for?
Do it right, or do it twice.
Edited 5/14/2003 11:04:06 PM ET by ELCID72
Replies
check if they have a compression type valve with a loose washer...
Would the old Chicago style faucets cause the same thing? Like if you only turn them on part way?
I have this vibration in the hot water pipes (old galvanized) that the neighbors can hear. It goes away if you open the faucet all the way.
Sure would like to know how to fix this. Sounds like it's gonna break something.
DRC
yeah... check your cartridges
"Watering the back yard seems to cause it a lot." Are they using a pulsed -tsch-tsch-tshc-tshc type sprinkler head?? Same effect as the loose washer mentioned.
Actually they use a shoop-shoop-shoop sprinkler head :)
Ok, I had ruled out the hot water side because the dishwasher doesn't make the noise. Checking for a loose washer on the outside faucet will be easy, but what about the toilet and washing machine? I can't imagine that all three would have the same problem, so is it possible that one loose washer is making noise when any one of three devices ie used? And the pulsing sprinkler...is it causing an unsecured pipe to vibrate?Do it right, or do it twice.
Hey Elcid72, excuse me if I'm stating the really obvious, but you know there's anti-hammer devices you can solder into a pipe? Lot easier than tracking down a loose pipe, especially as you can put it in where the pipes are available for working on (ie. basement).
Regards,
Tim
No, that's not too obvious to mention...I did see those with several connection options, but where does I put it, I asked meself. Concrete slab on grade, and the incoming line is buried in the slab. I suspect it surfaces near the water heater. Did you know you can buy the anti-hammer devices with solder connections, two different sizes of compression, cpvc, even one that goes on the back of the washing machine.
Went by the house today, and of course we couldn't duplicate the noise. Tried watering the back yard, ran the washer, flushed the 'mode, nothing worked. She admitted it's not a constant problem, but it is loud when it happens. Asked her to let it bang for a while next time, and try to find the spot on the wall closest to the noise. Also asked her to write down what they were doing when it happened. Young couple, two real young kiddies, first house I think. Just moved here from Utah.
Do it right, or do it twice.
Edited 5/15/2003 11:59:08 PM ET by ELCID72
I tend to trust solder and avoid compression, but thanks for the info on different fittings.
Sorry, I wasn't thinking about slab...it's all basements where I am.
I'm no plumber, and this advice is free, so it's worth a lot less than 2 cents (maybe I should be paying you before I give it? {G})...but presumably you've got a cold line somewhere near (after feeding) that water heater that's available. For the price of the anti-hammer device ($10?) and the time to solder it in (15 min?), I'd forget about getting the client to listen for the banging, etc, I'd just install it and charge them parts. Heck, you've already used up some of your earning time making two visits. I'd tell them if the problem is fixed, they can pay me the labour on it when they call me for the next job (nudge, nudge). Oh, and Mrs. Customer (don't you find it's the wife that makes these repair decisions?) don't forget to mention what a great guy I am to your neighbors...here's my card.
Regards,
Tim
Edited 5/16/2003 9:11:32 AM ET by TRIMBUTCHER
I thought those anti-hammer gizmos had to be attached near the tap. Are you are saying that they can be attached more upstream where you have access (without opening a wall?). That would be good news for my air-hammer problem.
No, arrestors upstream of the problem valve don't do much good. The water in the part of the pipe between the arrestor and the valve would still get slammed to an instant stop, which is the heart of the whole problem. An arrestor farther downstream can help if it's not too far. In that case, the closing of the problem valve would send the momentum of the moving water upstream against the inertia of the stationary water between the tee and the arrestor. If that isn't too much inertia, the downstream arrestor helps.
-- J.S.
Actually my daughter had the same problem in a new house she bought two years ago. The hammer primarily happened during the cycling of the outside lawn irrigation system. It turns out that she pressure of 70 plus pounds and the low voltage valves on the irrigation system we cutting in and out in a fraction of a second, causing bad water hammer. We hammered on the contractor who scratched his head a lot. The plummer came back to the job and opened up the drywall in the garage and installed a verticle three foot piece of capped pipe with a "t". The hammer stopped.
That three foot dry riser will work to stop the hammer until the air in it dissolves into the water, and the riser stops being dry inside. When the hammering comes back, she'll need to know that the fix is to turn off the main water valve to the house, and to open a valve somewhere below the dry riser (hopefully there's a hose bib handy). Let the water out of the pipes, close the hose bib, and turn the water back on. With the riser re-filled with air, it'll work again for a while. The hard part is making sure that the information about this little maintenance task is transferred to all future owners of the house.
-- J.S.
Went by today and replaced the faucet washers on both outside hse bibbs. The y are only 2-3 years old, looked to be in good condition, and were not loose. But we'll see what happens in the next couple of days. Each of the outside faucets has a back flow preventer attached (local code) that, among other things, lets the water in the hose drain out at the faucet end when the pressure is turned off. Not sure how they work, but I wonder if that could be the problem. Anyone have any insight into the innards?Do it right, or do it twice.
It's been a week since I changed both outside faucet washers, so I called to see if there is any difference...unfortunately yes...they seem to hear the banging a little more frequently now...esp from the downstairs commode and washing machine (about 10 ft apart). Help guys...need to find a way to solve this. The couple is young, short on cash, so I'd like to find economical solutions.Do it right, or do it twice.
Please excuse me if this has already been stated but I have this happen sometimes after working of a pipe if I turn the water of real slow so there isn't a big rush incase I didn't sweat it real good. Turning it on slow allows the water to fill up into the piece that is like a branch off to the side that is for air. All I ever have to do is tun off the water and open all the lines. Then drain the lines by opening the lowest faucet in the house(usually the outside line in the back yard, or basement if not a walkout). Then turn the water back on quickly as to not let the air spaces fill up.
gee, I read all the ideas given so far and don't think I saw the main one that I've ever seen:
a bad compression washer in one of the faucets (I suspect the outside hose bib).
The tell-tale is that it goes away when the valve is full-open.
Replacing that one washer (or, what the heck, replace all of the suspect ones to avoid a call-back) should solve it.
Washers only last so long, and depending on the local water chemical make-up (and what quality they were when originally installed) it might be time to replace all of them.
Norm
Several answers...I'm not saying that the remote arrestors do any good, because I have never used one (yet). All I was saying is that there are about 5-6 different connection types available, including one for the back of the washer. It is clearly advertised to be installed at the water inlet, and has the same garden hose fittings as the washer hoses. Hey, for the $10 it might be worth installing one in an acessible location to see if it works.
Someone mentioned bad washers early in the thread. That's why I turned on the sprinkler to see if I could duplicate the problem.
The pipes have been drained recently. The way I got involved in this, the buyers were of the opinion that the water heater had to be 18" +/- off the floor, so among other repairs I raised the heater. It's an electric heater not located in the garage, so I don't think it has to be elevated, but they insisted anfd I took the money. In the process, we drained the tank so we wouldn't have to lift 40 gal of hot water, and we opened an upstairs faucet to help it drain. Once it was in place, we bled off the trapped air at a couple of faucets as the tank refilled.
Why would you put the arrestor on a cold line downstream of the heater? Why not on the heater supply line?
Do it right, or do it twice.
El Cid,
Water hammers are caused when a fast flowing slug of water in an enclosed space (like a hard pipe) is suddenly stopped from flowing. this sudden stop sets up a pressue wave that jolts a pipe making a noise. If all your pipes are solidly attached you may not hear the water hammer even if it is present.
Most WH'es occur at the clothes washer because it uses fast acting valves or the toilet for the same reason. Use two arrestors at the W/D and one at the toilets. If your toilets are "stacked" one at the top of the stack feeder should be enough. Placing arrestors at the water heater does not do much as the W/H acts like an arrestor because of it's large volume to surface area.
It is almost impossible to turn an ordinary faucet (gate valve type) off fast enough to hammer. A gate valve will "sing," "stutter," or "machine gun" when the rubber gasket inside flaps in the flow of water turning the flow off and on really fast (acts like the reed of a wind instrument or harmonica.) They don't "sing" when fully open because the flap is not big enough to effect the flow.
Water hammer arrestors act by giving the fast moving plug of water a "spring" to de-accelerate slowly against. they should be placed near the fast acting valve for best results.
To prevent water hammers when installing plumbing... at the washer hookup install 2 arrestors or plumb with 3/4" all the way to the connections (slows down the rate of flow [linear feet per second])...use plastic connection lines from the angle stop to the connection(extra long helps)... use plastic tubing from the main 1/2" feed to the refrigerator icemaker connection...plumb with all 3/4" (waste of hot water anywhere besides the washer)...insulate all pipes and mount firmly (can't hear WH's when they occur...place arrestors at the ends of all long pipe runs... plumb an expansion loop into all long straight runs.
What you can do as a retrofit...replace all toilet and sink feeds with 3' long plastic hoses(even though manually operated valves don't cause WH's, the flexible hose will absorb some of the shock of any "hammers" in the system)...put arrestors at the washer hookups...slooowly turn on all other faucets to see if they "Sing" and replace gaskets as needed... last, and only if needed, put arrestors wherever convenient to get to.
I know how hard it can be to isolate a water hammer if you are not living in the house yourself... these suggestions should fix the problem in an effecient way as you can considering the value of your time.
good luck, SamT
Sam T has covered it!
Another post for the FHB Frequently Asked Quetsions file (whenever that is created)
Norm
:oD
what is the incoming pressure? Last year, similiar problem, the plumber finally replaced the pressure regulator. It was the last thing he did. Owners kept telling him the pressure regulator was only 3-4 years old. the noise called "Herman" never came back. Best of luck Jim J
Sid
Water hammer is from water running fast, stopping quickely, that jerks a loose pipe and then bangs it against the wood framing.
High water pressure will make it worst, lowering the pressure will stop it. If you have a regulator lower the pressure to 60 to 70 pounds. Pressure in the Los Angeles area goes up to 30 pounds higher at night.
All inspectors (contractors& homeowners too) of plumbing should grab the water pipes and shake it. If the pipe is not secure, shaking it will duplicate the noise of water hammer.
A quick fix for water hammer at the laundry is to turn down the faucet so less water is flowing. Disadvantage is it takes longer to fill the tub and the washer may wear out quicker. Or slightly plug up the screen in the washing machine hose.
Gordon
Two thoughts: see if the water purveyor will come out and check the pressure, and install hammer arrestors on the hot & cold washing machine inlets. But what about the commode? That can't be cycling fast enough, can it?Do it right, or do it twice.