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have you checked to see if the element has continuity. from what you are saying the lower stat works fine but it wont heat thats beacuse the element is bad. if your heater is known for high scale it will build up around the element causing it to over heat and burn out shut off the power to the heater and disconect both wiers to the element and test for continuity if no sound the element is bad
i recomend if the heater is old 5 years of bettter replace both upper and lower stats as well as the upper and lower elements
it is verry possible the line became broken in the jacket this can happen if it over heats the wire gets brittle and breaks. if the heater is older then 5 years get a new on ( just recomendation ) if not and you have electrical ( sounds like you do ) fish a new wire down to the element but first try to test for continuity from the upper stat wiers to the lower stst wiers first
one more thing is there a reset button on your lower stat ( they are usualy on the upper one ) if so see if it triped first
most electric heaters the top element heats up first then the lower they usualy never heat up at the same time first the top goes on then the botttom goes on afeter it senes temp
does the upper stat have a jumper between any of the tyerminals
What are the stats set at ?
Try turning the lower one up all the way to see if we can get it to come on.
OK I'm understanding that terminl 4 is the lower right side terminal on the upper stat ?
Is that right ?
There is a reset on each stat or just the upper ?
OK then heres what is happening, just had to make sure you had the typical setup.
, the red reset button should kill both circuits and both legs of power.So if one element works they both will.
The jumper bar jumps power from the limit switch to the upper thermostat. then if the sensed water is cool the upper thermostat will energize the upper element and hold the lower one off until the thermostat opens ( temp rises on upper element ) .
When it opens it sends power down to the lower thermostat and if the lower is calling it will energize the lower element. On a cold tank of water you won't get both elements. How long did you leave it sit after changing the elements ?
I know it sounds back wards of how you would think it would work but thats how it works but both elements don't work at the same time on your heater. If you turn the upper one down as low as it will go and the lower one up as far as it will go and let it brew for a little while you'll see the lower stat energize when the upper satisfies.
What was your initial problem ?
I found a diagram of it. It shoud help explain what I'm trying to say.
Here's where I'm going with this, there is a chance that the elements and the thermostats were not the problem to begin with. Your initial conditions sound like it was the dip tube in the tank , it sounds like it broke off sending all the new cold water to the top of the tank instead of the bottom. Therefore , when you would run water the hot water would seem to run out real fast because the cold water was barely being heated before it short circuited to the leaving pipe. All the while you probably had hot water at the bottom of the tank. Even now you will probably still have the same problem until you replace the dip tube.
There was some trouble in getting back to you.
The diagram is typical of a two element single phase residential water heater, they don't operate in unison or simultaneously. Just had to verify that with how many limits you had and where the terminals were. I think you will probably find that your dip tube is broken off tomorrow. If not them its really just a matter of the tank being scaled up. Either way though let us know how it turns out.
Hi Van ,
Glad I could help.