I am having problems with my waterheater decreasing the amount of
water as I take a shower, meaning the longer the shower is the less
hot water I have. Talking to some people I thought it was one of the
elements, I tested both meters with the power off and one wire
disconnected and they both read infinite to the mounting bolts and
around 15 ohms across the terminals. Do these readings sound right,
the stuff I read on the web said it should read what I meausred.
Any other suggestions the only things I can think of is the
thermostats, or there is allot of crud in tank. Is it a good idea to
drain the water heater and refill it to get rid of any build up? Also
everything I read said to test the thermostats but I can't find any
instructions on the procedure to test these. The model is a Richmond
Miser model #8V5-2C 220V 50 gallon. Thanks for your help
You really should do that about once a year, A lot of people never
I would give it a try, I think if there is a lot of crud around the heating
elements it will not heat properly.
Although the Soon to be X Girlfriend said she never did it, and her mother
never did it , in the 12 years they had the water heater, so I guess that
makes it right......LOL
Less what? Are you describing flow rate or temperature?
Your element resistance measurements are quite normal.
IMHO crud buildup in electric water heaters doesn't cause anywhere near
as big a problem as it does with gas heaters, and I've never seen much
buildup on electric heater elements I've pulled. I think the big problem
crud causes with gas water heaters is that it forms a thermal insulating
layer on the bottom of the tank which can let the flame overheat the
tank bottom and also interferes with transfering the BTUs to the water.
If you're experiencing a "too soon" decrease in water temperature, you
should check the dip tube on the heater's cold water inlet. That's a
pipe (usually plastic) which directs the entering cold water to the
bottom of the tank. If that tube falls loose, the cold water enters at
the top of the tank and finds its way over to the hot water outlet too
You can usually see the dip tube through the upper element hole with the
aid of a flashlight. If you can push on it with a thin stick and it
doesn't flop around loosely, then it's likely ok. The "proper" way to
check it is to disconnect the cold water inlet piping from the tank and
lift the dip tube up out of the inlet port.
Jeff Wisnia (W1BSV + Brass Rat '57 EE)
"My luck is so bad that if I bought a cemetery, people would stop dying."
I doubt if it is the crud in the tank, but draining it (not the tank,
just the crude, generally a few gallons) is not a bad idea. Some is likely
to not drain out, but you should be ahead. The only down side is sometimes
the cheap valves they put on those things go bad, especially if the have not
been opened in years.
A thermostat is a good chance. Next time someone is taking a long
shower, check for voltage (240V) at each element. If you get it on both,
that will eliminate that one.
Another issue would be the dip tube.
One last issue, is you are just using too much hot water and the tank
can't keep up. Most likely a problem if you don't have flow restricted
Thanks for the help
Ok to answer a few questions, the water pressure stays the same I just
find myself having to keep adjusting the faucet to keep the shower at
a reasonable temperature. It didn't do this until recently. I usually
take like 10-15 long showers at the most and as the only person living
here with a 50 gallon tank, and the shower as the only thing running
first thing in the morning I find it unlikely that I am using all the
hot water that quick. I did drain the tank out today and even filled
it partially and redrained it to make sure that it was flushed well
and the problem presists. I am going to check the thermostats
tomorrow and get a voltage reading on them and then if that looks
right I will pull the elements and look inside at the dip tube, and
maybe change out the elements while I am at it providing they aren't
First, crud in the bottom is bad, but it doesn't stop water heating
until it builds up so high that it touches the bottom element and then
it can cause the element to burn out. Try to drain some water out of
the tank if you want, but if you have hard water you won't get much
out with a regular valve; the only way to get really bad build up out
is to take out the bottom element and vacuum the stuff out through the
Second, lots of water heaters never had dip tubes and they worked just
fine, so something with the dip tube is not likely to be your problem
but could be.
Third, we assume you have at least two elements in the hot water tank.
A 50 gallon tank should deliver water hot enough to burn you for as
long as you want to take a shower unless you have an unrestricted
outlet. (assuming the thermostats are set at 130 to 135 F degrees.)
The standard 2 gal per minute restriction will certainly deliver
plenty of hot water.
Fourth, water heaters are pretty simple but you have to understand how
the electricity is routed sequentially to one thermostat and one
element and then through the other thermostat and to the second
element when there is high demand (temperature in the tank
decreases). All you need is the electrical diagram and a test
light(120 V to ground)to see if electricty is going through the
thermostats and if it is going through the heating elements. But you
probably need a check list to understand what you see.
For just testing the thermostats, turn the power off, disconnect one
wire at a thermostat and test for continuity across the two terminals
with your ohm meter. If you don't get continuity then turn the
thermostat lower (assuming that the tank is hot) until you get
continuity. If the tank is hot and you still can get continuity, the
thermostat is bad.
Send me a private email if you wish and I'll send you an old test
diagram and procedure (warning, it's a little slow if you have a
regular modem like I do).
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