Water heaters....GFP?

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Rick,

Thanks for the pics. I'm still confused though. The housing around the element looks like stainless steel, so if the element fails, shouldn't it just trip the OCPD?
 
When the outside steel barrier fails the water comes into contact with the conductive element within. Usually with a fair amount of resistance often leaving the circuit live and not tripping the breaker.
 
Thank you. That's what I was missing. I was thinking that the element would fail and make contact with the steel barrier. I was not thinking about water leaking in. I learn something new every day!
 
This sort of ground fault protection IMHO might even make sense from an energy savings and cost savings perspective, not just a safety perspective.

I don't know how common this is, but I keep reading (here and in other forums) about faults in heating elements that allow current to flow to EGC or to piping. The fault current is limited by a portion of the heating element, and thus never gets high enough to trip a breaker. Further the fault current bypasses the thermostat, and thus the current flow _continuously_. The net result lots of power consumption, a very high electric bill, and little benefit to the customer (the water is somewhat warmer).

If such fault are common enough, then the cost of ground fault protection for these breakers would be less than the average cost in wasted electricity of these faults.

-Jon
 
RICK NAPIER said:
When the outside steel barrier fails the water comes into contact with the conductive element within. Usually with a fair amount of resistance often leaving the circuit live and not tripping the breaker.
Click to expand...

If the outside steel comes into direct contact with the inner resistance element, then you may still have sufficient length of resistance element to limit current to below the trip point of the breaker.

-Jon
 
Jon,

I agree with you on all your points, except the part about the warm water. When this

happens the water will get very, very hot if the element is broken on the leg that the t-stat

switches, because the other leg is energized all the time.
 
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