I replaced a top element on an electric water heater ( double element) at
the cottage. We use lake water that is pumped up to a holding barrel above
the heater then feeds the heater. After replacing the element it took quite
a long time ti get water to run through the system to the tap, air pockets I
guess. The new element burned after a short while , it may have been due to
the air pockets and not much water in the top part of the tank.

Question: this heater has a thermostat for top and bottom element, should it
not turn off the element if it gets to hot , either if water is present or
not?

GINO wrote:
I replaced a top element on an electric water heater ( double element) at
the cottage. We use lake water that is pumped up to a holding barrel above
the heater then feeds the heater. After replacing the element it took quite
a long time ti get water to run through the system to the tap, air pockets I
guess. The new element burned after a short while , it may have been due to
the air pockets and not much water in the top part of the tank.

Question: this heater has a thermostat for top and bottom element, should it
not turn off the element if it gets to hot , either if water is present or
not?



It's very common for the thermostats to go bad over time also. I always
replace the other element and both thermostats when I have problems. I
then run the water until it comes out normal before I turn the power
back on. It's just extra work to replace one element and then another
and then a thermostat and etc when you can do them all at once and it
will last a long time. Sorta like replacing all the hoses and belts on
your car--you don't want to get broken down.

J

Gino: No. The thermostat senses the water temperature, not the element
temperature. So, no water at the upper levl, no cooling of the element. I'd
bet it overheats and melts down in just a few seconds if no water. Next time
run the hot water till all air is out before applying power to the tank.

Dave


"GINO" wrote in message
.. .
I replaced a top element on an electric water heater ( double element) at
the cottage. We use lake water that is pumped up to a holding barrel above
the heater then feeds the heater. After replacing the element it took quite
a long time ti get water to run through the system to the tap, air pockets
I guess. The new element burned after a short while , it may have been due
to the air pockets and not much water in the top part of the tank.

Question: this heater has a thermostat for top and bottom element, should
it not turn off the element if it gets to hot , either if water is present
or not?

No, for several reasons.

1) The heat transfer of air and water is different. A heater element
in water will distribute the heat a lot faster. Heater in air will
rise temperature very fast.

2) The thermostat is touching the wall of the tank. The heater element
is inside the tank. If the element comes on surrounded by air, there
isn't enough heat transfer to the thermostat. The thermostat stays
cool, and the element fries.

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"GINO" wrote in message
.. .
I replaced a top element on an electric water heater ( double element)
at
the cottage. We use lake water that is pumped up to a holding barrel
above
the heater then feeds the heater. After replacing the element it took
quite
a long time ti get water to run through the system to the tap, air
pockets I
guess. The new element burned after a short while , it may have been
due to
the air pockets and not much water in the top part of the tank.

Question: this heater has a thermostat for top and bottom element,
should it
not turn off the element if it gets to hot , either if water is
present or
not?

Thanks guys,
I'll go up next weekend and try another again, maybe change the thermostat
at the same time
"Dave" wrote in message
...
Gino: No. The thermostat senses the water temperature, not the element
temperature. So, no water at the upper levl, no cooling of the element.
I'd bet it overheats and melts down in just a few seconds if no water.
Next time run the hot water till all air is out before applying power to
the tank.

Dave


"GINO" wrote in message
.. .
I replaced a top element on an electric water heater ( double element) at
the cottage. We use lake water that is pumped up to a holding barrel above
the heater then feeds the heater. After replacing the element it took
quite a long time ti get water to run through the system to the tap, air
pockets I guess. The new element burned after a short while , it may have
been due to the air pockets and not much water in the top part of the
tank.

Question: this heater has a thermostat for top and bottom element, should
it not turn off the element if it gets to hot , either if water is
present or not?

How long it takes to get the air out of the hot water tank is
irrelevant. What is important is not turning the electric back on
until the tank is full of water and the air is out. If the element is
not surrounded by water, it will quickly burn out.

Unless you have reason to believe the thermostat is bad, I wouldn't
screw around with changing it.