We have sound of water still running slightly in two bathrooms by faucets at sinks, tubs, and toilets. But no water on. No similar sound is heard by kitchen or laundry room faucets. Leak detector at water meter moves ever so slightly when water meter on but not when water shut off at street. So definitely leak somewhere. But no water found. Husband has spent day ruling out that not hot water heater, kitchen dishwasher, washing machine, outside hose bibs,ice maker. He thinks in cold water system. But how do we find leak and how to fix it? House was built in 1973 and has copper pipes. It never freezes here in Southern CA so what could this be and how to find leak to fix it? Hope it isn't a slab leak. Right now husband shut off water at street so no sound heard. But whenever he turns water back on it is there again, noisy as ever! Thanks for any helpful ideas on how to troubleshoot this. The shut off valve for water to house does not work, frozen tight for twenty plus years husband says. God bless.



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"Leak detector at water meter moves ever so slightly when water to house turned off"...
then the leak has to be before the meter and you hear noise telegraphing thru the pipe ????
in other words, there is no way the leak detector can turn with the water off. (unless the turn off is not working)

You RE describing a slab leak, (even through you state that the meter runs with the house valve shut off), and 99% of the time it is a hot water pipe.

Usually there is a shut off at the house. What happens when you shut that ball valve off. If this valve is not a ball balve but instead a gate valve, Gate valves notoriously leak by. Replace it with a ball valve and then shut it off to see if you hear the water movement. You could have a leak in the service between the meter and the house but you will not be able to determine this until you have a ball valve installed where the water line enters your house. One other thing you should know. Here in most Southern California Cities copper is no longer acceptable to be rolled in under the slab. Many new slab installations are Post Tension Slabs where sleeved cables are installed in the slab and are streached putting tension on these cables. They help keep the slab from cracking or settling. But when your home was built copper was installed in and under the slab. These installations are a source for leaks and as one of the guys said, hot water is the usual culprit because of a chemical change when water is heated and its reaction on copper tubing. I have had this very problem in my Carlsbad CA home. My solution was to reinstall my copper lines into my attic. So install a ball valve where the gate valve is installed and listen to see if the leak is outside of your home. Good luck.



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Thanks for your reply. Husband clarified to me this morning that water meter leak detector does not move when wate at street turned off. Shut of valve to house is frozen tight and hasn't worked in twenty years he says.no water sound all night as water shut off at street. Husband just turned water back on and noise of running water louder under master sink than other bathroom sink. But master is only sink with water turned on to worm and husband has to go to work today and needs to shave there first.



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Thanks for your reply. Unfortunately, shut off valve to house is frozen tight and hasn't worked for twenty years husband said. I asked about turing that off too yesterday but he couldn't. Sorry to hear you had similar problem in copper pipes. How did you find your leak there?

Susan, while in the master bedroom talking to my wife, she said I hear water running. Being a Plumber I immediately went to the closest fixture which was my master bath lavatory and put my hand on the carpet so I could get into the cabinet, the carpet was warm so I immediately went out to my hot water heater and shut off the cold water valve coming into the water heater. When I did this, my wife yells out, "you fixed it". I immediately knew that I had a leak in my hot water line under the slab. Instead of tearing out concrete, I went to HomeDepot and purchased new copper tubing to repipe my water into my attic. This required opening up the walls so I could come down from the attic to the fixture. It was a big mess for a day or two but I finally was able to turn on the water again and not worry about wasting water from tubing under or in my slab.

One note: when I brought the copper tubing home from Home Depot and I started to make my first cut to length, I noticed tiny pin holes in a line, in my just purchased copper tubing. I was livid and took the faulty copper back to Home Depot and complained that if I had not noticed these tiny holes, I would have installed a sprinkler system in my attic and the damages would have been multiplied ten fold.

This was all done a few years ago and Home Depot was buying their copper from Mexico and they had no quality control on their purchases. If I were installing copper in the attic I would use Type L which is more expensive because it has a thicker wall than Type M which has red markings on the tubing. Type M is legal according to code but I would choose L for longivity. Do it once and sleep at night.

BTW Susan I see a Dr before your name. I don't use Dr in front of my name but I am a retired Nuclear Drain Surgeon, (plumber from San Onofre Nuclear Generation Station in San Diego)



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you need to call a good licensed plumber for your problem which sounds like a slab leak, and absolutely if your area is not subjected to freezing and you are planning to stay in your house i would bite the bullet and get the water distribution out of the slab because often times once they start you have repeat performances every year or two.

Yes, I agree we need a good plumber. Now that water is back on a while, I have found water mark and dampness on interior upper cupboard portion under right side of sink about eighteen inches inside of bathroom against wall to master bathroom. But husband later clarified that was caused when he tried to replace turn off valve under that sink faucet. It took photos over time and the mark is exactly the same so not from any leak from these strange sounds. We still don't see any sign of water leaking anywhere!



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That is great that you have the talent to fix that problem. Although we have contacted plumbers here now, noise in pipes like water on when it isn't still remains. It only goes away when water shut off at street. Wish we could turn it off at house to see if it disappears too but that valve frozen. Wish we had a plan to determine if slab leak of not. We still don't see any water! Water heater not turning on much and no hot spots so not hot water leak here. But what is it?

So there is a good update on our situation here. We did get valve loosened and now able to shut water off just to the house while leaving the main valve on at the street. Mysteriously, the sounds of slightly running water under the bathroom sinks disappears and all it quiet! I take this to mean that we do not have a slab leak but a leak somewhere between the main valve at the street and outside somewhere in the yard. Is this a correct assumption? Thank you so much for telling me about the importance of shutting off just the water to the house to be able to get those sounds to stop! My husband insists that very same valve was frozen and was unable to be turned even when my Dad was still living and helped him do the water heater years ago. So I figure Dad was helping from heaven to get that valve to easily loosen with just a little lime remover applied and allowed to sit for a couple of hours tonight. I figured our hard water deposits are what made it seem so tightly shut. Husband said it turned easily after trying the lime remover. Then we checked and sounds in house gone but leak detector at street still moving the same little bit as before. We did this twice just to make sure and same results. So now I am thinking tomorrow's search will be for a leak somewhere outside. Am I making the correct assumption that because now there is no sound in the house anywhere but leak detector still moves that the leak is not in the house but somewhere outside? We have turned water off at the main shut off at street to get rid of any movement of the leak detector so our water bill won't be any worse than it already will be because of all of this. Thanks so much for listening and sharing your ideas.



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With the house valve off, street valve on, have someone watch the indicator while the house valve is turned back on. See if the indicator speed increases. Turning off the house valve and the noise stops sounds to me like there's 2 leaks. One on the house side of the house valve and one on the street side.