Heating costs can be extreme in the winter, but a solar air heater could help keep the costs down. This video will show you how to wire a snap disk controller in a safe manner, to be used in a solar air heater or any other application. This is intended for people not familiar with electronics. Anyone who already knows how to do safe wiring may find it too simplified - though electronics enthusiasts might enjoy the journey.
For an example of a bimetal snap disc thermal sensor controller, check out the Electrical Temperature Control Circuit on rimstar.org. Also, see the Window Solar Air Heater (indoor to outdoor airflow) and Window Solar Air Heater (outdoor to indoor airflow).