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Blown Elektra Microcasa Heating Elements

Postby doubleOsoul on Sat Mar 12, 2011 10:16 pm

I have two Elektra Mcals - one 1984 and the other 2003. The older one blew it's heating element at Christmas and this morning my newer second one blew it's heating element as well :( . Is it bad luck, is this intrinsic to the Mcals or am I doing something wrong? I have my lever plugged into a power bar and nothing else.

Thanks for all your input...:)
I'm so bad I kick my own ass twice and say nothin' about it...Dolemite
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Postby orphanespresso on Sat Mar 12, 2011 11:55 pm

On the face of it I would say it is bad luck...but there may be more going on as you have possibly changed electrical grids lately.
The question is WHY does an element burn out in the first place? I know that you are both observant and careful so it likely is not due to running out of water and melting it down but look at Ohm's law, v=ir (voltage =current x resistance). This equation ALWAYS stays in balance in any circuit. Now, when a resistor (heating element) is cold, the resistance is LOWER than when it is warm or hot. Since the r variable goes down, given the same voltage the i or current will increase when the element is cold vs the rated resistance. This is the reason that a light bulb always burns out when you switch it on, the filament (resistor) is cold and therefore is momentarily exposed to more current than usual, and if the filament has become thinned due to loss of metal molecules over time then pffft, the filament burns through at some weak point due to the increased current on the wire.
Then, consider the electrical grid...where we are our voltage ranges from 115 to about 125 volts so given the constant resistance of the heating element as a factor of temperature (and geometry of the resistor), then the current will be different at these different voltages by ohm's law once again. So take a worst case scenario when the element is cold and you turn on the machine right in the middle of a power surge, the effect on the element or resistor would be amplified. This is one good reason to plug the machine in through a surge protector just in case, to hopefully avoid this scenario.
Ideally, the element would be slowly brought up to power by use of a variac type approach when you slowly bring up the current until the element is warm enough to run on the rating but that is a bit extreme.
Also, check to see if the element is actually burned....may just be shorted at the terminal ends and can be fixed.
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Postby doubleOsoul on Sun Mar 13, 2011 12:24 am

Doug,
Thanks so much for the quick reply. You're right, I'm tight on basics like water levels and such. The first burn out was a surge that wasn't protected by a surge protector. I learned that lesson - once. This unit has always been on a power bar which I switched off and unplugged after use (overkill but I wanted to avoid the potential of a surge).
I will flip it over in the morning and see if the problem is at the terminal ends.
Gosh... heartbreaking! I'm trying to leave for San Francisco in a few days and this added future cost is a real debbie downer.
I'm so bad I kick my own ass twice and say nothin' about it...Dolemite
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Postby DrDregs on Sun Mar 13, 2011 3:36 am

I think it's in Doug's post somewhere - but do you let the element cool down before adding water? Continual refilling with cold water over a hot element will eventually make it dead. But you probably knew this.
"24 hours in a day, 24 beers in a case. Coincidence? I don't think so."
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Postby doubleOsoul on Mon Mar 14, 2011 12:23 am

Say DrD,
Yep, I sure did. I baby that chrome beauty. Anyway, I'm gonna have to suck it up and go shopping at Orphan Espresso and that's that.
I'm so bad I kick my own ass twice and say nothin' about it...Dolemite
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