Janko Gorczynski
Janko Gorczynski voted up Ancient Hippy's answer

The reason to shut off the electricity to the heater is for shock reasons. The temp adjustments (2) are at the upper and lower coils. Risk of shock is great at these two points. Your heater is on a 220v breaker. If you are unsure, just shut off the main breaker in your box. That … Read more