Burnt Electrode

Any ideas as to why my son's electric hot water heater electrode burned open? It was cathastrophic!
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Al
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I used to maintain many hot water heaters on Alaska's North Slope at the two 500 man construction camps, CC2 and CC1 and later at the 1500 man camp, Prime Camp from 1976 to 1982. Almost all hot water tanks' electrode failures were attributable to a buildup of sediment in the tanks. We finally started a routine flush down process to remove the sediment.
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This one was about a year old. Could the sediment build up that fast?
Al
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wrote:

Yes, it can. I lived where the water "ate" my elements in less than a year sometimes. You might check out the manufacturer "Watlow" and some others for a stainless or coated version. Flushing the tank periodically will help, but your element is still suspended in a chemical bath no matter what you do.
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Maybe someone turned the water supply off, allowed the tank to drain and left the power applied to the element. That would burn it out quickly.
Al wrote:

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"
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wrote:

There are several questions that need answers. 1. Did the top and bottom elements burn open or just the bottom? 2. Are they using treated water or well water without a softner? 3. Was sediment found in the bottom of the tank?
Sediment that surrounds a element will cause it to over heat and burn open. However, if the water level dropped below the elements both should overheat and burn open.
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I think he poster who suggested that the unit was turned on before it was filled with water was correct. The fusing would have prevented an immediate failure, but the element must have suffered some damage which eventually became catastrophic.
Both elements as well as the controller were replaced just to be safe. The symptom was that the hot water temperature had declined. I suppose it was running on just one element. And, unfortunately, this all happened after the one year warrenty. grrr!
The water is city water and dunno about the sediment.
Al
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