I'm still skeptical about the anode being the problem.
I've heard of anodes being a problem with smell. The usual reason given is
that they encourage bacteria growth which releases hydrogen sulfide. I've
never seen it happen myself. My inlaw's water has that smell, but it's fr
om a well, and in both the hot and cold water. The hot water is worse of c
ourse because it volatilizes. But while I haven't seen it, there are lots
of articles that say it happens.
But how does an anode release air? It can't be the HS gas. There's only a
tiny amount dissolved in water, it just happens to affect our nose very ea
sily. If it were concentrated enough to burp at a faucet, it probably woul
d be enough to kill you. For sure it would corrode anything nearby, probab
ly eat through pipes.
I haven't seen anyone suggest any other gas that an anode can produce. Wel
l, long ago there was a report of hydrogen in a water heater, but I tracked
down the original report and it turned out to be something else, long stor
And if it were any other gas, I don't think the OP would be reporting it as
air. Does it smell at all? Will it burn?
And if it were some other kind of bacteria reacting with the anode, and it'
s making enough gas to burp, I'm not sure I'd want to drink it. Must be li
ke jello inside, with that much bacteria.
How about this for a scenario? Your well pump is injecting air into the wa
ter supply. You actually have air in both hot and cold water pipes. BUT,
you never notice it in cold water for two reasons. Cold water dissolves mo
re air, and your cold water pipe layout has some areas where it gets trappe
d. Your hot water tank has a dip tube for cold water entry, but hot water
leaves through the top. Your water sits in the tank long enough for air to
separate and form a layer on top of the water.
The thing is, an anode is a pain in the butt to get out. They're usually s
crewed in really tight. And even if you get a shorter one or segmented one
, you still need clearance to get the old one out. I wouldn't try this exc
ept as a last resort.