My gas hot water heater is making a high-pitched whining noise in the
evenings. This has happened two nights in a row at about 7pm. No
water using appliances had been used, nor had anyone in the house used
the shower or tub in the hours before the noise. The first time it
happened, I turned on the hot water in the kitchen, and the sound
stopped. I thought that was a fluke but tried it again last night.
Sure enough, the sound stopped abruptly as soon as the water in the
kitchen got warm after I turned it on.
Does anyone know what the cause of this might be and if it is
dangerous? The water heater is about 7 years old and it was pre-
installed in my manufactured home that was built in 2000.
Thanks in advance for any help,
City water supply?
It could be very high water pressure,
especially if there is no thermal expansion tank.
7 years is average heater life in some areas.
It is possible that there is a pinhole leak in the tank.
If you don't see any evidence, the leak could be in
the central flue where you won't see it.
Next time it happens, check to see if the burner is on.
That may rule in/out gas as the cause. Sometimes
the pilot burner can make oises, but running the water
should not affect the pilot.
Yes, we are on city water. And, the floor around the water heater is
I don't know if I have a thermal expansion tank - I'm really not
educated when it comes to this type of thing. So, I guess my main
concern is if its a potential safety issue.
I will check to see if the burner is on next time it happens - if I
can find it LOL.
Look carefully to see if there is a little dribble coming out the TP
valve (Temperature & Pressure on the side near the top of the tank with as
pipe going down almost to the floor. You might even try touching it to see
if you can feel the sound. I could be building up too much pressure in the
tank due to no pressure release and too much pressure in your home.
It also could be build up of deposits on the bottom of the tank. As
noted in some areas 7 years is a good life for a tank. It depends on the
local water conditions.
The pressure issue can and should be addressed. A weak TP valve is easy
and cheap to replace. Not much you can do after the fact about the build
up. That usually means it is time for a new heater as would any actual
I just did a tested the TP valve, and it it releasing pressure (I can
hear water draining out of the pipe connected to it). There is no
leak, not a dribble. I also just checked all of the connections I can
see for leaks and I do not see any.
So, would you think the TP valve is weak if it works quickly and
properly to relieve pressure?
I'm a little concerned about needing to replace it since all the
paperwork states that this hot water heater (http://
waterheating.rheem.com/oem/catalogRes_detail.asp?id!) is designed
specifically for MF homes. So, I'm not sure I can go to Home Depot
and just purchase any correctly sized HW heater.
So, when do I know if it needs to be replaced. When it explodes,
starts leaking, or stops providing hot water? I certainly don't want
to wait for option A to happen.
Thanks again for the replies,
OK you found the problem, but it may be one of two problems. It may be
the TP valve itself, I am sure it can be replaced and it is likely a
standard valve, but I really don't know. But it may also be doing exactly
what it was intended to do and the pressure or temperature is going to high.
Do you have a drain valve? If so try to find someone to loan you a pressure
gauge that fits it and find out what the pressure is in that tank. Also can
you hold you hand in the hot water coming out of the kitchen faucet?
An additional note. Don't force that drain valve open if it you have not
been draining the tank on a regular basis. They use such cheap valves on
most tanks that they tend to break easy. Not a fun thing to have happen.
I've learned alot about my water heater today and am posting what I've
discovered in case anyone else reading this thread is having the same
First, this HW heater is not available at Lowes or Home Depot, because
it is designed for MF homes and has a direct vent. Apparently this
makes it harder to find. Both of those stores recommended going to a
plumbing specialty store, which likely means a higher cost to replace.
But, I called the folks at Rheem, who are the makers of this HW
heater, and they said that the sound I'm hearing is probably related
to thermal expansion. They recommended installing a thermal expansion
tank. They also said that I should have a drain and flush done on the
HW heater. So, I guess if the sound keeps happening, I'll be calling
a plumber to do these things soon.
Thanks for the help,
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