New Water Heater equals Air in Lines?

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It was just one possibility that was suggested. I don't think it's necessarily a likely culprit either. Problem is there just doesn't seem to be any good explanation and the anode, if it can be removed, is pretty easy to rule out.

 I've never seen it happen myself.  My inlaw's water has that smell, bu t it's from a well, and in both the hot and cold water.  The hot water is worse of course because it volatilizes.  But while I haven't seen it, th ere are lots of articles that say it happens.
Agree, that's my understanding too.

ery easily.  If it were concentrated enough to burp at a faucet, it proba bly would be enough to kill you.  For sure it would corrode anything near by, probably eat through pipes.
I agree. I don't have an explanation for what possible chemistry could account for a reaction at the anode. Here is another thought. What happens if you have a bad electric heating element that has the electric element in contact with the water? That would produce oxygen and hydrogen. Maybe that is more likely than some kind of reaction at the anode. Might be worth seeing if air shows up with the tank turned off.

racked down the original report and it turned out to be something else, lon g story.

I would think any gas that's observed, absent anything unusual, would be reported as air, because that's what we tend to think of as "trapped" in a water system.

e like jello inside, with that much bacteria.

 BUT, you never notice it in cold water for two reasons.  Cold water di ssolves more air, and your cold water pipe layout has some areas where it g ets trapped.  Your hot water tank has a dip tube for cold water entry, bu t hot water leaves through the top.  Your water sits in the tank long eno ugh for air to separate and form a layer on top of the water.
Something like that is theoretically possible, I guess.

ed one, you still need clearance to get the old one out.  I wouldn't try this except as a last resort.
The anode should come right out of a new tank. I got mine unscrewed on a 5 year old tank without anything special. If it's 15 years old, that could be a whole different thing.
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TimR wrote:

I think that is a very interesting theory, although I doubt the part about "your cold water pipe layout has some areas where it gets trapped". But, the idea that the hot water tank is a place where the pumped-in air can get released and trapped seems plausible to me. And, if cold water holds more trapped gases than hot water, when the gas-infused cold water gets heated in the hot water tank maybe that releases the dissolved/trapped air.
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One big hole in that theory is why this phenomena only started right when the water heater was replaced and not with the old one which would have identical characteristics with regard to trapping air. I'm thinking my electrolysis by a bad heating element sounds better. I've never heard of that happening, but it sounds theoretically possible, no?
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snipped-for-privacy@optonline.net wrote:

Good point. I was actually thinking of adding the far out possibility of inadvertent electrolysis to my post since it is an electric hot water heater. I had even started looking up electrolysis of water (which I generally think of as involving DC rather than AC current http://en.wikipedia.org/wiki/Electrolysis_of_water ), and wondered if there was some type of spurious leak of electricity causing the water to break down into hydrogen and oxygen. And, I tried searching for electrolysis with AC current instead of DC. I am not so sure that AC will really produce hydrogen and oxygen from water, but I don't know for sure.
But, if the "air" coming out of the hot water spigots really is a mixture of hydrogen and oxygen, I guess holding a flame near the spigot could produce some interesting results -- hopefully just a popping sound and not a real explosion. And, I guess there would be no smell to the gas as there would be if it was hydrogen sulfide gas.
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On Thursday, March 7, 2013 4:23:17 PM UTC-5, TomR wrote:

If you use DC, you get hydrogen at one electrode and oxygen at the other.
If you use AC, you get a mix of gas.
BUT, your water has to be conductive. You need to add enough salt, acid, lemon juice, etc. to let the current flow. Pure water won't conduct.
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He did say his water has a lot of minerals. That sufficient.
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On Thursday, March 7, 2013 4:07:51 PM UTC-5, snipped-for-privacy@optonline.net wrote:

I've never heard of it happening either, but it seems like a good idea to check it.
If it's electrolysis, it is splitting water into a stochiometric mixture of oxygen and hydrogen.
Just put a small plastic bag over the faucet, turn it on, and collect some of the gas. Test it with a match or lighter. Hydrogen mixed with the ideal ratio of oxygen should definitely burn.
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e ideal ratio of oxygen should definitely burn.
Maybe she'll light up like one of those faucets from the folks that have nat gas in their water from fracking.....
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On Thursday, March 7, 2013 4:37:54 PM UTC-5, snipped-for-privacy@optonline.net wrote:

Could be fracking, too.
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One big hole in that theory is why this phenomena only started right when the water heater was replaced and not with the old one which would have identical characteristics with regard to trapping air. I'm thinking my electrolysis by a bad heating element sounds better. I've never heard of that happening, but it sounds theoretically possible, no?
If it's electrolysis, then one of the elements is leaking electricity into the water and this situation becomes a safety issue. The current flow will eat away the element materials at the point of contact and the problem will get worse fast. At some point, electricity will be felt in the water depending upon the quality of the ground via pipes, water and wiring. Don't do a hand test in the water to find out though -- use a neon tester or a meter and watch what you touch. As the current increases, a breaker should trip.
From a safety standpoint though, check this out right away.
Tomsic
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There is a far simpler possible answer.
When the water heater was replaced, all the hot water pipes drained and fil led with air.
Most of it came out, but a little continues to be trapped and causes the sp it and gurgle. It doesn't take much air to do so, and it can be a pain to get the last little bit out.
Occam's Razor, anyone?
Now, for electrolysis. I just doubt it can produce enough gas. I can see two obvious ways to test for it.
Capture some of the gas. Fill your laundry tub halfway with water, put a c lear plastic bag inside it, can be a dry cleaner bag or similar. It doesn' t have to hold pressure. Open the bag under water so it fills. Run a hose from the hot water faucet into the bag. The air/gas/whatever will collect . Poke a small hole in the top of the bag, squeeze a little gas out and use a lighter to check.
If it does not pop, it is NOT electrolysis. If it does pop, electrolysis i s not confirmed, it could still be methane from the well.
Second way: If it is electrolysis, somewhere you have a circuit completed through the water. The element is 240 V, just two hots, no neutral. The c ase exterior is grounded. So electrolysis would require jolts to leak from the element through the tank coating to the metal body and back to the pan el through the ground. The voltage would be 120 of course, not 240. Put a clamp on ammeter on the bare ground wire. You shouldn't measure any curre nt. Disconnect the ground wire, and if it is electrolysis it should stop. You might be able to measure voltage between ground wire connection and gr ound wire with them disconnected. (I always get in trouble here with voltm eter measurements.)
That would mean you have a bad element AND a bad tank coating on a new tank , and it just seems unlikely.
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I may have been too skeptical about electrolysis.
I googled and found a case where someone was getting air in the lines, and solved it by raising the water heater off the concrete floor with insulation.
His theory was current flowing from the element to the floor through the water. A concrete floor is normally considered effectively at ground potential.
I don't know what else would account for that fix working.
It does seem if you had that much current flowing, you'd quickly eat a hole in your tank. That's what corrosion is.
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ion.

ential.

I don't know how that would account for it working, unless something else is very wrong. The WH should be grounded via the AC wiring and whether it's sitting on the concrete floor should have no effect.

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On Saturday, March 9, 2013 8:47:49 AM UTC-5, snipped-for-privacy@optonline.net wrote:

Water heaters run on 240V. That's two hots, no neutral, no ground. They'l l work fine if the tank is not grounded although of course it is supposed t o be. There's a risk of somebody getting a shock if somehow one of the hot s does short to the case. The case would then be hot with respect to the f loor, or with respect to you if you were standing on the floor.
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wrote:

Water heaters run on 240V. That's two hots, no neutral, no ground. They'll work fine if the tank is not grounded although of course it is supposed to be. There's a risk of somebody getting a shock if somehow one of the hots does short to the case. The case would then be hot with respect to the floor, or with respect to you if you were standing on the floor.
Ah, yes. When I lived on a farm some years ago, the electric hot water heater in the house shorted to the tank which was not grounded for some reason. The voltage appeared on the water pipes which were fed from a well and pump in the barn. On their way to the well, the pipes were connected to metal stanchions of some 20 dairy cows who used metal water cups fed by the pipe.
Our first clue that something was wrong was when the cows got jumpy and stopped giving milk. We then started getting slight shocks when touching faucets in the house or the barn. I got out the neon tester and found that the tester would light up with one lead on any water pipe and the other lead on a wire made out of a metal coat hanger that I stuck into the ground. The climax came when I brushed a bare ground wire from the house electrical panel against a water pipe by mistake. The sparks flew and the water heater breaker tripped. It was a miracle that we didn't electrocute either a person or a cow. And, yes, we did install solid grounds on the pipes and bonded them to the electrical panel ground too.
Later, we found a rupture in the water heater heating element probably due to a lightning strike.
Tomsic
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On Sunday, March 10, 2013 6:37:31 PM UTC-4, = wrote:

It seems likely to me that if you have current flowing from the element to any part of the tank, you will quickly erode one of the contacts and destroy either tank or element. If it is to the tank itself, you're going to corrode a hole in it.
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roy either tank or element.  If it is to the tank itself, you're going to corrode a hole in it.
Have you seen the vaporizers that you use to humidify a room when you have a chest cold? Some of them are just two electrodes seperated by about 1/2" that go into the water in the plastic container. They rely on the circuit being completed by the water, current flowing which then heats the water. The electrodes don't erode, at least not enough to keep them working for a very long time. And you can't get electrocuted because the electrodes are covered by a plastic shield, you can't touch the water in the container when the electrode top part goes into it, etc. I think the instructions say something about adding a bit of salt if the water is unusually pure and it doesn't start heating on it's own.
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On Monday, March 11, 2013 11:11:34 AM UTC-4, snipped-for-privacy@optonline.net wrote:

I'd forgotten about those.
You have a point. I guess I was thinking DC, which WOULD quickly erode a hole.
They don't produce any electrolysis though, do they? At least not that I've heard. It's been a long time since I've seen one.
As far as grounding a hot water heater, what I said was correct. You are required to do so as a safety feature. BUT, they will heat water fine without grounding; they only need two hots to function.
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On Monday, March 11, 2013 11:20:17 AM UTC-4, TimR wrote:

hout grounding; they only need two hots to function.
Just googled these steam vaporizers.
The modern ones use carbon electrodes. I found an owner's manual for an ol der metal electrode one. According to it, the water needs to have some min erals to work, and if not then add salt. But if there are too many mineral s, or you add too much salt, too much current flows and the electrodes quic kly corrode.
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Running on 240V does not negate the need for a grounding conductor. An electric water heater must be grounded.

Above you said no ground?

Uh huh, which is why they must be grounded unless they are installed incorrectly.

Which is what may be going on in the water heater under discussion. With the resistance element in contact with the water, he would likely be getting electrolysis of the water into hydrogen and oxygen.
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