On 04/29/2017 11:08 AM, Jim Wilkins wrote:
wrote in message
....

Which use begs the question of why OP would leave the AC energized
once it's even remotely close to freezing, anyway...a solution
looking for a problem here.

....

I guessed that it was a DIY solar water heater. ...

Probably better guess--I see on reading again what I skimmed as
AC" was "AC power"...

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