Our third and final design placed the button in indirect contact with the water within the tank. Our heating element is in series with the photovoltaic cells and the button thermostat, but the button is placed in between the inner and outer walls of the water tank. We accomplished this with a hole saw and some electrical connections. The button will be placed on the outside of the internal tank, but inside the outer shell of the water tank. This means the button thermostat will not be sensing the temperature of the water directly, but the temperature of the tank should be very similar. We do not want to put the button in the tank because if the insulation fails the current flowing could be exposed to the water. Calibration after data collection will be done so we know the actual temperature of the water when the button switches.
|Heating element with feed through that screws into drain.|
|Drain hole where retrofitted element screws in|
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