Here is the problem that I got. A couple of months ago the water pressure started to drop in the kitchen. Now the hot water heater is making this gurgling/rumbling noise. I've noticed in both bathrooms in a specific area the floor is warm compared to the rest of the floor, cold. I just started to noticing this morning that when I turn on the cold water, warm water comes out,then goes cold! Any thoughts??? Thanks!

Tye

 

I'm not a plumber (sometimes my pants make me look like one), but I need a little more info on your house. Is it on a well? Is it stick built or modular? How old is the water heater? Have you or do you have the capability to look and the water lines? My dad used to be in the contracting buisness and I figured I'll ask him.

 

Are the bathrooms on a slab?

 

House is on a slab. No well, city.

 

Go out side and look at your water meter. There should be a little triangle or really small needle on the face of the meter, it's called a leak detector. If it's turning, you are using water. If it's spinning and all your fixtures are turned off, turn the hot water tank off and in an hour or so, check that warm spot on the floor and see if it's cooled off. If it has, I hope it's a new house and less than a year old cause you have a leak. Good luck.

 

When you turn on the hot by itself, does it have more pressure than the cold by itself for a split second and drop to normal quickly? Wondering if you have lime buildup causing it to back up? Is there a check valve in the cold supply line?

 

You can try cleaning out the Water heater.. If it sounds like there are rocks churning in the water heater it is lime build-up... Put a hose on the drain valve and drain it hopefully getting all the lime out...

What it almost sounds like is that it is to hot.. do you have the temp turned all the way up??? if it is a bubbling sound then you may be close to boiling your water heater and backing the hot water into the cold water lines... (hot water expands).. This can be caused by 2 things.. (1) your rod and tube is full of lime and deposits and not monitoring the temp properly.. (2) thermostat has just gone out of Calibration (very rare)...

Are you getting any blow off from the temperature relief valve??? (hope you have one)...

 

I had a similar thing happen to me when my hot water heater went south. One of heating elements was heating all the time and would over heat the water. The expanded water had gone back into the cold side. I was getting the gurgling noise. But I had really hot water coming out the hot side at the faucet.

 

GERRY's hit the nail on the head!!!... I was typing a reply when he posted before I finished...

One thing I'd recommend that Gerry mentioned about draining the scale...

The boiler tank drain valve is virtually USELESS for getting any meaningful amount of scale out of the tank. WAY too small an opening without removing the entire drain valve, as the valve plugs up with pieces of scale all too quickly.
After I removed the crappy little plastic drain valve, I connected up 2 joints of 1" PVC pipe with a 1" PVC union to the drain port(s) leading out to the driveway... (it's probably a 1/2 NPT conn or 3/4" at best for the drain valve where it goes into the tank, so get a reducer to attach to the union) Try to make the PVC line as straight a shot as possible with few 90's to prevent plugging of your "purge" line.
Turn the water supply back on full blast and go outside and watch the humongous stream of gypsum "corn flake" slurry come blasting out... You will still likely have to repeatedly turn off and unjam all the scale that plugs up the 3/4" NPT port. (hence the union!)
I had to reach in with needlenose pliers and break up a particularly troublesome chunk that wouldn't make it thru the 3/4" drain port.

After I did this the first time, after the flakes dried, I swept them all up in a pile on the sidewalk and I was astounded there could be that much stuff in the tank and it still functioned

That's why I had much better luck the next time blasting all that crap out of there by plumbing my 1" PVC "purge" line up to the 1"NPT lower electric heating element port. Much MUCH better and quicker... No pluggage...

Then, on top of that,... I found I had even better luck at getting virtually ALL the remaining stuff out by blowing intermittent blasts of compressed air back into the drain valve to agitate the sediments(via the garden hose that is also blowing water/flakes.)
Messy, yes.. but it sure got the piles of hard water scale "flakes" out.

This may sound like the "Tim, the ToolMan Taylor" method but it works well w/o removing the heater from the water lines...

I've only changed the one heating element, and one T-stat since I bought the house in '92. I periodically listen for any "rumbling, thumping" to tell me I need to do it again.
SO far, So good...

K.

 

Hey Tye, Hate to say it but it sounds to me like you have a slab leak. If your floor is warm in one particular area that would indicate a hot side water leak in the slab. Also the fact that the water comes out warm first then goes cold indicates that it has some circulation on the hot side. Call me if you get in a bind. I usually don't go that far but I can make an exception. First thing that you should do though.... make sure that everything in the house is shut off. Go outside and look at your water meter. On most meters there is a triangle shaped flag that spins when the water is running. Even a moderate drip will make the flag move. Check the flag to see if it's moving. Again.. call me if you need some help.

<edit> Just saw that totally rad already told you about the leak indicator.

 

That's ok SB, I like to start with the easy stuff myself............at least as far as diagnostics go.

 

Thanks guys! I just got home and saw the responses.

Gerry, that's kinda what I was think'n, about the lime build-up. So I'll drain the tank tomorrow.

Jeff, I was kinda think'n the same thing about one of the hot water pipes leaking. Is that an easy fix or??? Doesn't sound like it.

Thanks again guys!

 

I would be surprised if they ran the pipes in the slab... do your pipes in the bathroom come out of the wall or do they come out of the floor.. If they are out of the floor then yea they are in the slab.. In the wall then I would think that they circle the house in the walls..

The new stuff I see being built has all the pipes in the walls if it is a slab.. Under the house if it is a raised floor...

If you are in fact pushing hot water back into your cold pipes Make sure that there is a Pressure relief valve on the water heater!!!! If the lime has built up around the rod and tube thermostat then the Thermo fuse link safety may not since the temperature and shut the water heater off if it over heats.. If this happens and there is no Pressure relief valve.. Well bad things could happen...

Gerry

 

I see slab leaks all the time. Theres 2 ways to fix them. You can either find the exact spot where there is a leak ( the most difficult way) and cut the concrete slab in that spot.Or if you know that it's on the hot side you can abandon the slab pipes and run new pipes through the attic and down the bathroom and kitchen walls. You can also run them on the outside but it isn't pretty. If you know somebody with an infrared camera that would be a great way to check. A Flir camera can spot a leak really easily through the slab. I can't afford a $15000 camera so I don't have one. A cheaper way to check would be to get a laser thermometer and check different parts of the slab. See how much warmer that part of the slab is. Gerry I'd be suprised if the pipes weren't in ths slab. That's how they do it here. You won't see them coming out of the floor because they come in inside of the wall framing. Yep Tye it's going to involve some work and some drywall repair. Hopefully you will find something different but it sounds like a slab leak.

 

I agree slab leak.
I use to install Radient floor systems along with in slab plumbing. If you have a warm spot in the slab then you most definately have a leak.

Do you have hot water at all your taps.
Do you have good pressure.

Is your water runnig into the HWT (hot water tank) all the time when not in use. This will represent a leak.

What I would do is shut off the hot water tank. Drain it completely, do the service on it as others have said. This will ensure long life for the tank.

Next I would fill the tank with with water. Leave the power off to the tank. Turn on your hot and cold lines to see if the problem with cold water being warm goes away. Also see if the heat starts to go away in the warm area of the floor.

The bad thing on this issue is that the floor will have to be cut up to fix the line, and or new lines installed.
Problem with not going into the floor is that you do not know how much damage is under neath, soil missing etc.
I recommend that you mark the warm spots with chaulk, then carry on with the above in reguards to the tank. And then either higher a pro to come in and cut your slab up and fix it or do it yourself.

Good luck with it,