Hot Water Leak?????


Old 07-21-07, 08:10 AM
Thread Starter
Join Date: Jul 2007
Posts: 3
Angry Hot Water Leak?????

OM After having no hot water~ I have spent the past two days trying to fix a hot water heater, BUT after testing out everything and replacing thermostats, etcÖ now I think I have a leak in a hot water line.

I'm in Florida, built on a concrete slab and have no idea where to start. I see no apparent leaks, but if I turn off the cold water input to the hot water heater the water does get hot, as the hot output pipe gets VERY hot. As soon as I turn on the cold water to the hot water heater I can hear water flowing through the hot water output and with in seconds the hot water output pipe cools down and there is NO hot water in the house. Listening carefully to the shower walls I can hear (what seems to be) water flowing, but if I turn off the cold water flow to the hot water heater that sound stops.
My reasonable deduction is I have a leak, BUT how do I find it????
How can a leak get fixed under the house????
I can just bet this is BIG BUCKS and you guessed it, Iím pretty well BROKE!
Any and all help would be greatly appreciated, Thanks in advance~

Cheryl aka:Cmoore
Sponsored Links
Old 07-21-07, 08:51 AM
Join Date: Nov 2004
Location: CA
Posts: 2,041
I am not real clear on your description, but it does sound like a leak. Do this: turn off all your faucets. Go look at the water meter. The little dial should not move at all. If it does, you have a leak. Leaks in underslab piping is common. Usually, a leak will manifest itself as a wet spot. But if it is underground, you may not see that rigtht away. You probably would be able to find a warm area on the floor. There are leak detection companies who can pinpoint the leak. That service will probably cost a few hundred.

The short term fix is to jackhammer the slab, when the spot is located, and repair the pipe. You may find that your homeowners insurance will cover the damage, that is the cost of taking up floor covering and jacking the slab. I have seen it where they cover everything except the actual pipe repair, meaning they covered 95% of the total costs. Check with them.

Often, if you have one slab leak, it means you are prone to further leaks, and repiping in the overhead is the ultimate solution. That is costly, and not covered by insurance.
Old 07-21-07, 10:58 AM
Thread Starter
Join Date: Jul 2007
Posts: 3
Thanks 594tough

I did as you said and watched the meter, as long as the cold water valve to the hot water is off, the meter does not move, as soon as I turn that valve on the meter goes nuts! So it pretty well confirms that I have a bad leak in the hot water lines somewhere, and I'm suspecting it's under (or in) the slab. I will have to contact someone to come and find it and really appreciate your input, sadly it seems it will not be cheep.

Do you know if the pipes are IN the concrete vs running under the concrete? I'm wondering if there is a way of doing repair from digging under the slab rather than jack hammering through.

I do have one more question if someone can answer, if I have to re-pipe the hot water lines does that also mean redoing the cold water lines also?

Old 07-21-07, 11:26 AM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Year ago I had to sledge hammer open a leak under a condo built on slab and located it by a method involving water pressure differential between two different plumbing fixtures in the condo. I extrapolated the difference in pressure relating to footage difference and found the spot to within about a foot of the leak. But you could try a stethoscope type method by using a metal tumbler drinking glass turned so that the rim edge is down and you listen by placing your ear on the bottom of the tumbler. Being that it is your hot water line, you know that it must go to some fixture. Try to figure out where it may go - the shortest path it may take - and lay down on floor and try to listen for it. Also, since it is lots of hot water leaking, perhaps an infrared thermometer pointed at the floor (these cost like $50 +) could pick up the hottest location.

BTW, in a trailer court I can hear water running slowly HUNDREDS of feet away by placing the tumbler on a copper water line in one trailer, so this is not just theory. I had a woman run her water as a trickle 300 feet away in rythmic patterns and I could hear it!
Old 07-22-07, 08:09 AM
Thread Starter
Join Date: Jul 2007
Posts: 3
Thanks for your help ECMan,
As hard as I tried yesterday itís impossible for me, to find out where the leak is. The problem is your method and comments are correct, every area I listened to it sounded like Niagara Falls, even trying to keep the water flow into the tank at a minimum the sound of the leak is traveling through every pipe (and the floors).

594tough, Thanks for the hint about the insurance,
Although I doubt my insurance is going to cover this, who knows I might get lucky. (Allstate, Panhandle Florida, weíve been hit by three hurricanes, and my policy is very vague in regards to any and all water) Shoot, I might be better off if the flowing leak has caused a SINKHOLE!

Does anyone know how far piping normally runs from the outside walls of a house? I live in a single story ranch and apparently the hot water pipe runs from my hot water heater (in the garage, rear wall) between two wall studs, through the studs footing and into the slab. From there it has to run down the whole back of my house to reach the two bathrooms, and at some point must T off to bring the water to the front of the house (kitchen and laundry room). I canít seem to pin point how far the pipes are from the back wall of my house and I canít imagine that they stay under the footing for the wall studs. My biggest fears at this point are that the leak is under one of my tubs or God forbid under my fireplace. But then again I donít think there is any good place when there is a leak under a slab~

Iíve tuned off the cold water input and killed the power to the hot water heater since, from my deductions, the tank empties out partially and I donít want anything else to burn up in the tank. Iíve called a plumber to come out Monday morning and hopefully they will be able to find it.
Iíll keep you posted, not that you really care, but it may help someone else down the road if itís posted on this forum. BTW: Thanks everyone for participating in this forum, itís very helpful to me to know I have a place to get answers and potentially solutions.

Cheryl aka:Cmoore1954
Old 07-22-07, 09:29 AM
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 8,629
Originally Posted by cmoore1954 View Post
...through I’ll keep you posted, not that you really care, but it may help someone else down the road if it’s posted on this forum. BTW: Thanks everyone for participating in this forum, it’s very helpful to me to know I have a place to get answers and potentially solutions.

Cheryl aka:Cmoore1954
But we DO care. I wish everyone would post back after we suggest things.

On car repair radio call-in show this weekend the 2 hosts asked some people to call back so they know how suggestions turned out, as they said it cannot only help other people with similar problems but also help the hosts in future diagnosis.

What kind of floor covering do you have between that run of the garage and bathroom? Any carpet you can disconnect form the tack(less) strip and roll back to see if there is one particularly more heavy spot of moisture?

If I was at your house, I would do that, and if need be get out my pressure gauge and hook up to water heater drain and take reading. Then undo it and take gauge to bathroom sink and take another reading and compare, and start doing the math, like I did in that one job I explained, and then re-lay down on the floor and really carefully listen.

You say you believe water runs near the outside of the house? And no water at all is visible along that wall outside the house?

I am willing to bet this repair will cost you a fortune. And that being the case, if this was me, and I knew that the leak was say within some 30 foot? run, I might take a spot and hammer through the slab, after doing my viewing and math, as stated, and hope for the best, and do it again and again, maybe 3 times - because mixing up some concrete patch and re-filling the bust outs may pale in cost/aggrevation, to what your bill might be with licensed plumbers, depending on where you live. Usually rates go up a lot when they KNOW you need highly specialized detection equipment. Just like when sewer rooter man knows you need camera inside pipe to inspect and charges you $150 just to take a peek. I see a thousand dollar bill, give or take a few hundred here, and depending on your finances, the decision is up to you. If you go the pro route you may want to get other estimates depending on if they quote you a price. Ask each plumber what equipment or method they will use to find leak and how this will affect the charge. Maybe someone can find you the leak and you can opt to do the repair, as a compromised alternative.
Old 07-24-07, 07:12 PM
Join Date: Jul 2007
Posts: 1
man51 is right

you say that it sounds like a water fall,well here is what you want to do turn the valve off till you can't here any thing,then crack the valve open just a hair and listen. if it is just a small amount of water going though the pipe it makes it easier to locate

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes