Have an emergency? our drainage experts are available /. Great customer service! very trustworthy people!! The typical electric unit is wired to a -volt circuit to heat the water, the current passes through electrical-resistance heating elements—usually two, one at the middle of the tank and one at the bottom. Horizontal bars form the main design of the stelrad caliente creating a sleek and stylish look - perfect for bathrooms and living areas alike! Brenda.