Solaren cylinder, with a smooth inner surface of the lime and resistance to bacterial growth. Solaren Boiler provides cathodic protection via magnesium anode. Titanium doped double-layer enamel coating the inner surface of the boiler has been in the double protection against corrosion. Made with CFC-free polyurethane insulation solaren boiler. Heat loss is minimized. Cylinder outer plate is coated with electrostatic powder coating technique.