Air bubbles from hot water faucet

David_54

For several months I have noticed an effervescence or air bubbles coming from my bathroom sink hot water faucet when I first turn it on. It looks like fizzy soda water for a few moments. The bubbly water clears after a second or two. Fill a cup with it, the water is bubbly and clear and the bubbles quickly dissipate. The bathroom faucet in question is the highest point in the plumbing system. I assume that since air rises, it's collecting here. Any idea what the source of the air bubbles is? Anything to be concerned about? Conventional HWH is about 5 years old. Pipes are copper. Water supply is municipal. Thanks to all!

hot_rod

those are called micro bubbles. They can form when water is heated, or by a restriction in the piping, out gassing caused by anode rods, and by the aerator on the faucet.

Try removing the aerator as a simple first step, they pull some air into the water to help keep from splashing in the sink.

Maybe the water company has changed treatment chemicals and it is reacting with the anode rods forming a gas?

a 5 year old tank, it may be worth pulling and checking the rods anyways.

lchmb

any chance you have a domestic expansion tank on the system? Could have a slow leak

David_54

I do not have an expansion tank on the system. It's really not much of an annoyance. Is there any health hazard or are the bubbles just air?

Larry Weingarten

Hello: Very good chance it's hydrogen gas made by the anode in your tank, as Hot Rod mentioned. It's not a health hazard unless you collect the gas and try to light it! Do you soften the water? That would speed up the anode and produce more gas. If you wanted to isolate the problem, you could remove the anode and install a temporary plug. Wait just a few days and if the gas is gone, you'll know it's the anode... which should be checked periodically anyway.

Yours, Larry

4Johnpipe

The water treatment may require a different anode rod than the standard with the tank.

David_54

How does one specify a different material/type of anode rod? Also, I've never removed one before. Is the rod the full length of the tank? If so, I don't have enough ceiling clearance to get it out.
Also, to determine if the gas is Hydrogen, I suppose I could hold a lighter near the faucet. There isn't much. If it's only air (doesn't burn), it may change the analysis.

hot_rod

Any fracking nearby, maybe you have some of the combustible water

At the top of the anode rod it will either be smooth, or have a weld dot to identify aluminum or magnesium.

try www.waterheaterrescue.com

Larry hangs out here and wrote an excellent book on water heaters.

It may be in the bookstore here also.

David_54

No fracking nearby anywhere. I live in a well-established community in Michigan that sources its water directly from the Great Lakes (North of Detroit, not Flint, btw). The water is processed in a typical filtration plant. Our water is tested and reported annually. It is way better than average in all aspects. Tastes good too. I would not consider the water to be too soft or too hard. Soap washes off with ease, no slippery leftovers or feeling on skin. No mineral deposits or rust either. If I were to replace the anode, I don't have adequate ceiling clearance to remove the existing. Do they bend? Saw it off in sections, etc. One suggestion was to clamp at the tank with vise grips, then saw off piece by piece. Afterward, replace with flexible version.

hot_rod

it will bend, one time. It depends on how much "meat" is still on the rod. When they deplete you end up with a steel wire, very easy to remove.

Replacement one are segmented, looks like a string of sausage.

At the website I mentioned, they offer electronic versions also, that would eliminate odor potential.

David_54

It would be easy to install either a segmented or electronic. Is Magnesium preferred over aluminum? Does the electronic unit ever have to be replaced on a multi-year cycle, or is it good for 10-20 years (assuming the electronics don't fail/doesn't die, etc)?

Larry Weingarten

Hello: I definitely prefer magnesium to aluminum... which I believe is a health risk. Magnesium also protects the tank better as it generates more current. The powered anode should last for many years.

Yours, Larry

David_54

regrettably I can't use a powered anode. Turns out my Bradford White Hydrojet tank has the anode paired with the hot water outlet. Complicating matters is that my tank is hard-piped with Cu, not flex tubes. It may be tougher to remove.

David_54

I did find out that BW tanks use magnesium, though. Not sure what makes/models of 50 gallon tanks have separate anodes. Wish this was the case...