I have a gas-fired water heater. I'd say it's 30 gallons but I'm not
sure without checking again. I'm not sure how old it is, it was in my
house when I bought it a couple years ago. When we moved in, 4-5
people could shower within an hour or so in the morning and everyone
got hot water. Lately, the third shower is often cold. I nudged the
thermostat up a few degrees and that helped a little but not enough.
I've heard that with electric water heaters and hard water (which we
have), the elements sometimes scale up or deposits accumulate in the
bottom of the tank, gradually decreasing the effectiveness of the
heater. I understand *that* can be address by draining the tank (and
the accumulated junk) and then refilling and letting it go.
Is there a similar kind of maintenance that can be done on gas-fired
heaters? If not, is there something else I can do besides replace the
TIA for any tips.
Yes, you should drain the heater to get rid of the "junk" that
accumulates on the bottom of the tank, that junk keeps the heat from
transferring as well as when it was new. Have someone stand near the
heater and see if it turns on partway thru the first shower. If it
does not, the thermostat may be faulty.
I'm having the opposite problem - this was evident when I moved into
my house. The water heater is 22 years old, so I suspect it is close
to time to replace it. The *first* shower of the day is cold; if you
wait 10-15 minutes between the first shower and the second then the
second shower is nice and hot. When I moved in, the thermostat was
set too low, and I had a bad T/P valve (which would cause it to pop
off after raising the thermostat setting) once I rectified that and
then set the thermostat for 130F water at the kitchen faucet after the
burner had shut off, everything was fine. Now I'm having the same
problem again, it seems like the water is allowed to cool down too
much before starting the burner - the first shower now is not warm
enough even if you set the control to all hot, whereas if you let it
sit and then try the hot water, it'll scald you. Is replacing this
control a DIY project, or should I just suck it up and start saving to
have a new water heater installed? I realize that it is a crapshoot
to keep repairing a water heater that's so old but I have no
indications that it's in anything but excellent shape, and I replaced
the anode a little over 2 years ago.
they tend to be close to a hundred so at that age I'd think hard about
a new wh. Replacing the control is not bad if you are handy. Check
carefully for gas leaks with soapy water. Usual proceed at your own
Update: it's a 40gal A.O. Smith manufactured in 2005. That means it
is outside the age range where defective dip tubes were common. I
guess draining it is an easy first step. I can't get to that for a
week or so.
Well draining cant hurt but start in early AM and allow all day.
If the valves plastic once opened it may never close again, and may nt
open enoughto get any trapped crud out. It will be stopped by the
So buy a cap that screws on the valve exit in case it drips since it
if little crud comes out the main valve thermostat is likely bad. they
can be a PIA to get out. Think rust in place.
I suggest you shop for a new heater in advance of disturbing the old
one in case it fails somehow.
I highly recommend upgrading to a larger capacity tank with a higher
A 75 gallon 75,000 BTU tank costs more but can provide nearly endless
In november 2000 I went from a 40 gallon 34,000 BTU tank to a 50
gallon 75,000 BTU unit, the biggest that would fit the available
Best move I could of made It was a 6 year guarantee tank but is still
going strong today, nearly 10 years..........
My bad, didn't read the subject. I'm thinking electric water heater.
But still with electric heaters they tell you to flush the crud out of
it on a regular basis and the heat isn't coming from the bottom?
The OP said several showers. If the tank is clean, the
burner will be adding heat while they are showering. If the
tank is dirty, the tank will run out of hot water, and the
burner will, slowly, reheat the water much later in the
Unless I'm really confused, there isn't a heating element in the water
(as in an electric heater), it's a gas burner below the tank. As I
understand it, the crud accumulates in the bottom of the tank and
essentially insulates the water from the burner.
On Wed, 27 Jan 2010 16:35:39 -0800 (PST), Christopher Nelson
I gotta 40 gal A.O. Smith (gas) that I installed in '93, still works
If yours is only 6 years old, I wouldn't start by draining. Just
take the plate off and watch operation of the unit whilst folks
are showering. Do the burners fire when expected? Does the flame
look like a clean burn? Etc, etc.
If needed, check the users manual (if any) or search the net
for basics of operation.
If all of that looks OK, -then- consider other suggestions in
this thread. If not and you can't sort it out, report back
"Law Without Equity Is No Law At All. It Is A Form Of Jungle Rule."
All of them can have that problem. It's easy enough to hook a hose up
to it and drain it. Make sure the gas is turned off to it or the
control is set to not heat at all. If you get a whole lot of small
white crumbly bits see the next paragraph.
One of the other common problems is the disintegration of the plastic
tube inside the tank that causes the cold water to be feed all the way
to the bottom. This failure causes the cold water to start mixing
with the hot as soon as you start using it. The result is that the
water becomes luke warm pretty quickly and soon gets cold even though
the bottom of the tank has hot water in it. You can usually remove
the cold water inlet and attempt to slide this tube up. If all you
get is a stub then that's your problem. It is possible to get new
tubes but they can be a pain to install because a lot of people do not
have the head room over the tank to get the new one in.
Lastly it is also possible that the thermostat control is failing.
Those are replaceable but may or may not be within your skill set.
You have to replace that whole square unit where the gas connects and
wher the control knob is. They are not designed to be serviced and
usually have anti-tamper screws in them. Can be a little pricey and
depending on the age of the unit you might be better off with a whole
new water heater. If you are not certain then you probably ought to
get someone to do it. Mistakes with gas can become a big problem.
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