At Wit's End - Water Hammer Problem

[robertgb]

For about three or four years now, we have had an almost constant water hammer problem. I have had three different plumbers out to the house, plus the contractor who remodeled our bathrooms.

The contractor installed a large arrestor by our water heater and I've installed water arrestors in the back of our Kenmore front loader washing machine. The lines have been bled multiple times and one plumber tried adjusting the water pressure.

None of these things worked on more than a temporary basis. And by temporary, I mean a few days at best, a couple hours at worst. The hammer always comes back. Now when I bleed the lines, it no longer goes away. And it now also happens when the COLD water is turned on and off.

The contractor ripped into the tile in our new bathrooms (where the hammer sounds the worst) to check all the pipes and found no loose pipes or anything else amiss.

The problem seems to stem from the Kenmore front loader. I hate to wash clothes because every single time, the constant on and off of the water saver feature causes the worst hammering of all (although we also get hammer simply by turning on the kitchen or bathroom sinks). We were told by the Sears technician that this is a common problem with front loading washers.

At one point, the contractor adjusted the flow in our showers and that seemed to make the water hammer disappear, but it also made showering next to impossible, because the flow was far too weak. And forget a tub bath, if that's your thing.

Anyway, I'm pulling my hair out over this problem. Short of demolishing our $2,000 washer and throwing it off a cliff, or taking showers at a trickle, or re-piping the entire house, can anyone think of ANYTHING else that might help us solve this?

As I said, I'm at my wit's end.

 

[frodo]

you have a loose pipe, and the valve on the washer closes very fast. making the pipes jump
you will not get rid of your problem till you find the loose pipe that jumps when the valve on the washer closes

my personal shower was banging, where the pipe went thru the floor

I cut a wedge 2x4 peice and hammered in the hole. it stopped

 

[CT18]

Did the hammer start after the re model. If so what was added in the re model, new shower valve or new valve location. Is there a access panel where you can get to the shower divert er.

 

[robertgb]

you have a loose pipe, and the valve on the washer closes very fast. making the pipes jump
you will not get rid of your problem till you find the loose pipe that jumps when the valve on the washer closes

I wish it were that simple. The house has been checked for loose pipes, with holes torn in the walls and bathroom tile to check for them and everything is rock solid.

 

[robertgb]

Did the hammer start after the re model. If so what was added in the re model, new shower valve or new valve location. Is there a access panel where you can get to the shower divert er.

We did the remodel and got the new washer around the same time, so I'm not sure when exactly it started.

New shower valves were added in both bathrooms during the remodel and I can get to the valves and adjust the pressure coming through. That seemed to work temporarily but was adjusted so low we could barely shower. And then even that didn't seem to work, so I turned them back up.

 

[johnjh2o]

Have you checked to see what the water pressure is? You may need a pressure reducing valve.

 

[frodo]

we seem to be talking about 2 different things. water hammer occurs when a faucet is turned on, then off

nothing in between.if pipes rattle while valve is open. that is a bad washer/disc

please clear my confusion. does this happen ONLY when water is turned off/on or while it is running ?

 

[robertgb]

Have you checked to see what the water pressure is? You may need a pressure reducing valve.

Yes, all of the various plumbers tried that. No luck.

 

[robertgb]

we seem to be talking about 2 different things. water hammer occurs when a faucet is turned on, then off

nothing in between.if pipes rattle while valve is open. that is a bad washer/disc

please clear my confusion. does this happen ONLY when water is turned off/on or while it is running ?

I'm talking about when it is turned on and off. The washer is a water saver, so it turns on a spurt of water, then immediately shuts off, rather than simply filling the entire drum.

When faucets are turned on and off, we get the hammer. If you simply slide the faucet handle from hot to cold while its running (one handle faucet)... hammer time.

 

[frodo]

You have a loose pipe. just because they cant find it .doesnt mean it does not exist


is your house water piped from over head?

under the wood floor ?

under the concrete ?

is it pex ?

copper ?

 

[robertgb]

You have a loose pipe. just because they cant find it .doesnt mean it does not exist


is your house water piped from over head?

under the wood floor ?

under the concrete ?

is it pex ?

copper ?

It's piped overhead in the attic. Plumbers have checked every pipe up there throughout the house and have found nothing lose. You can hear the hammer sound in a specific area—which is why the walls were torn apart—and every pipe was secure.

The problem HAS gone away for very short periods of time and usually returns when the washer is used.

 

[KULTULZ]

...we seem to be talking about 2 different things. water hammer occurs when a faucet is turned on, then off

nothing in between.if pipes rattle while valve is open. that is a bad washer/disc

please clear my confusion. does this happen ONLY when water is turned off/on or while it is running ?

...hmmpf... scribble...scribble...scribble...

FACTOID OF THE DAY!

 

[frodo]

It's piped overhead in the attic. Plumbers have checked every pipe up there throughout the house and have found nothing lose. You can hear the hammer sound in a specific area—which is why the walls were torn apart—and every pipe was secure.

The problem HAS gone away for very short periods of time and usually returns when the washer is used.

I dont want to seem like I am arguing, BUT, If the plumber has checked everything and found nothing, He has not checked everything,
BECAUSE IT IS STILL HAPPENING

when he "Checked" everything, Did he do it while cycling the washer?

i would look where the pipe is passing thru a hole.

 

[robertgb]

I dont want to seem like I am arguing, BUT, If the plumber has checked everything and found nothing, He has not checked everything,
BECAUSE IT IS STILL HAPPENING

when he "Checked" everything, Did he do it while cycling the washer?

i would look where the pipe is passing thru a hole.

They cycled the washer. They turned the bathroom faucets on and off, thump, thump, thump, while another crawled through the attic pipe by pipe checking for loose pipes and the source of the thump. They found the "source" and then proceeded to tear down the walls. Everything was strapped in tight. But the sound continued.

The only solution they found was to turn down the flow on the shower valves in both bathrooms (the bathrooms are connected by a wall). It makes showering a drag, but after they bled the pipes again, the sound was gone. Until it wasn't a couple days later. So I tried bleeding the pipes again and the sound got marginally better but never went away.

So I turned the shower valves back up, and over the period of several days the hammer got worse. I tried bleeding the lines again yesterday and no success. I didn't unhook the washer hoses, however, to remove them from the water saver, so I'm going to try that today.

This has been an ongoing problem for a few years now and every plumber has been stumped.

 

[pcride]

I would recheck the pressure to the house at the hose bib outside, first. Then I would check the pressure at the washer, 1) while its running, this would be the running pressure, and then 2) with the valve off, static pressure. You may need a T fitting to adapt to the running line.

Although you haven't said what the pressure is, typically house pressure is around 50-70 psi AND you could have a faulty pressure regulator. I did.

Secondly, when does this happen, every time during the day or more at night, during the day or middle of the night? City water pressure varies as folks use water in the neighbor hood, this is why its best to water your lawn super early (2-3AM) when most people are sleeping.

My neighbor had the exact same problem and it was the pressure regulator. He replaced it and hammer went away. A pipe can be loose and not hammer, it hammers when there is a build up of pressure like when the valve opens/closes suddenly with lots of pressure behind it.

I had 140 pressure and with the water running was around 55. Typically you'll see 55-70 static pressure, then 30-40 running.

I've also heard of people hooking their sprinkler system right into the city pressure which is what they use to do "back in the day", I don't think its allowed anymore. I installed 2 pressure regs, one for the sprinkler system, one for the house.

 

[robertgb]

I would recheck the pressure to the house at the hose bib outside, first. Then I would check the pressure at the washer, 1) while its running, this would be the running pressure, and then 2) with the valve off, static pressure. You may need a T fitting to adapt to the running line.

The plumbers checked it, but I'll pick up a rain bird in the next couple days and check it myself. I hope to god you're right about this. I already have a T fitting.

 

[pcride]

Post back! it would be great to know. A few other points. If your pressure regulator is "old" , its another indication. The spring in them will eventually wear out and will let the full pressure in. If you end up replacing it, its nice to purchase the double union one vs the one that has only 1 union joint. Makes it easier to replace in the future. Its a bit tricky cutting the copper and getting the distance just right.

Also when you check the pressure, observe the hammer spike and what it registers on the pressure gauge. Check the pressure in the very early morning, during the day and evening when the neighbors are all home cooking and washing. If the pressure fluctuates between the readings, then its the pressure regulator for sure and it tells you that the city water pressure is controlling your water pressure.

 

[ExtraMilePlumbing]

I once went to a call where water was making a constant knocking sound.i followed it to the front, where I discovered it was the prv valve making that noise

 

[ExtraMilePlumbing]

Before you go tearing up you're house I will add a few water hammer arestors , good ones from a supply house not no homechepo

 

[pcride]

Before you go tearing up you're house I will add a few water hammer arestors , good ones from a supply house not no homechepo

I went to a plumbing house and bought 2
For $25 a piece.
It was the chief Sioux brand? Has a chief on it. Anyhow HD sold them for $9.99. Plumbing house is not always the best. There are like 2 main stream
Brands out there.