I've already posted this, but I screwed up the Subject line. My
husband passed away recently and my brain is only on half power.
Also, he used to take care of these kind of issues. Sorry about the
I noticed that within the past month or so I have a lot of air when I
turn on the hot water. As the water gets warmer the air gets worse.
Since it's only the hot water I assume it's a problem in my house, but
just to be sure I checked with my neighbors and the do not have any
problems. We have town water.
What could be causing this? The air comes out in strong bursts
sometimes and it makes the pipes vibrate.
On Jul 14, 9:03 am, " email@example.com"
My first though is a defect in the water heater. Air in pipes is
common after work is done, but I've never seen it last more than a
couple of days & only a couple of minutes if you go around and run
And we are sorry for your recent loss.
Wild guess: You have a defective thermostat on the water heater (or it's set
way too high) causing the water to boil. It is extremely unlikely that the
pressure would build sufficiently to rupture the tank, but it's not
impossible. You'd have to have TWO things wrong: the bad thermostat AND a
defective pressure relief valve. Still...
Another clue supporting this theory is the temperature of the water. If it
is REALLY hot - like steaming - the symptom lies with the water heater's
thermostat (probably). It IS possible the thermostat's temperature setting
got bumped when someone tried to store something next to it. Try turning it
Alternatively, if you're on a well, it could be pumping air into the
system - Nah, never mind, if that were the case you'd be getting air in the
cold water line also.
That's what the safety relief is for, and if it were boiling any
significant amount it would lift.
But, it could still be either maladjusted or malfunctioning and hotter
water will cause more air out of solution plus perhaps more nucleate
(localized) boiling on the heater (assuming electric) element(s)...
So agree first question is "is it hotter than normal?"
Air in water lines that are on city water can be a common occurence,
especially if you are at the end of the main line. When the pumps
loose power due to an electrical outage, or other reason, air is
produced thru what is called "cavitation" in the pumps volute. If this
is the case, there is not much you can due about it, other than
contacting your water company and see if they can (or are willing) to
either reduce the pressure slightly or take other measures. They way
want to know about your problem in order to maximize their delivery
and avoid other problems. Anyway, check with them before you call a
Hank <~~~~ Sorry about your loss.
Not too many, if any, municipal systems use pumps to supply the water mains.
They use pumps to fill gravity-fed tanks. This has several advantages:
* They can use a smaller pump and have it run when demand is low to get
ahead of the curve
* The water distribution system still works - for several days - if the
electricity goes off or the pump fails
* A gravity system maintains a constant and predictable pressure
I've got a relatively new water reservoir right down the street. It's 60' in
the air of course but the sucker is HUGE. The pole on which it stands is
round, concrete, and about 30' in diameter. The tank itself is also
concrete, about 60' in diameter and twenty feet high and must contain about
4.5 million gallons!
Every time I pass it, I think it would make a really swell dwelling with
just a few additions: Elevator, windows, gun ports, etc.
Here's what it looks like:
You are correct in most cases. However, there are relay stations and
booster pumps. In the district I am in, they use towers and booster
pumps. The air can be caused by the cavitaion of the booster pump.
I am at the end of a water main and I get air everytime the electric
goes out and sometimes when it don't. I was just adding my $.02.
The tower would make a great house if you didnt' mind all the damn
Hank <~~~too old for that many stairs
The OP said there are bubbles in the cold, but not as many. Suppose the
incoming water is saturated with dissolved air. If it stands in
cold-water pipes in the house that are warmer than the source, bubbles
will form. Even more will form in the water heater. Households using
more water might not notice it.
I imagine water wouldn't have that much air unless it was dissolved
under pressure. Could a municipal water system dissolve air in water
under pressure? Another possibility is that the dissolved gas was
generated in the pipes as a product of water purification. Could that be?
Anything is possible. The bottom line is that air is in the lines,
both hot and cold. If it were me, I'd call the water department and
see what they have to say about it before I call a plumber. If they
have a tower, I would think the air (if any) that may have been
produced in the purifying process would escape in the tower, but maybe
Water lines are pressurized and don't need to be layed in a sloped
fashion like sewer/waste lines. Her tap could be at a point a little
higher than her neighbors where the air could settle. Therefore she
would get air and her neighbors wouldn't. But again, anything is
Yes there is air in both hot and cold BUT, there is only a little
burst of air when I first turn on the cold water, before the water
comes out and only in the kitchen. This has been happening for more
than a year, and for some reason doesn't happen at all in the winter.
There is lots of air in the hot water, the worst being once the water
has run a while. No matter how long the water runs there are still
bursts of air and it happens everywhere the hot water is used.
It you get it at hot and cold taps, it sounds as if air is getting into
municipal pipe. It can happen when hydrants are flushed or pipes are
repaired. I don't know how it would get in every day.
Perhaps bubbles smaller than peas travel along the municipal pipe, and
the slope guides them to your condo and not others. When your cold tap
in the kitchen is off, just enough air collects to make a small pop when
you turn it on. When the water is flowing, the bubbles are too small to
In the water heater, the little bubbles would rise to the top and enter
the outlet as a larger bubble. That would explain why you hear big pops
while the hot water flows.
If the problem starts with little bubbles in the municipal main, I don't
know what would cause those bubbles.
I am sorry for your loss and I see that you have received some good
advice. I will only add one thing. You have been trouble shooting
this thing very well and you provided all the information that most
people would not have included allowing someone to give you some
On Jul 14, 3:37 pm, firstname.lastname@example.org wrote:
I do plan to have the plumber here within the next week or so. I just
would like to have some idea of what might be wrong. I hate dealing
with these things in complete ignorance. Sort of like taking the car
in for service and not even knowing how to check the oil.
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