Double glass coated tank for high temperature water heaters

A high temperature water heater comprising a steel tank for holding a predetermined volume of water to be heated, heating means associated with said steel tank to heat water therein to a temperature up to about 190 degrees Fahrenheit, said tank being constructed of steel welded parts and having fittings secured thereto, said steel tank having an inner surface wherein said fittings and steel welded parts form smooth edges with said inner surface to create a smooth inner surface, said smooth inner surface being coated with a first water resistant base coat primer of cobalt glass enriched with ZIRCON (trademark) which is heat fired, and a second high temperature water resistant glass coat which is subjected to a second firing and produces a hard outer glass surface which is highly water and corrosion resistant and has fine gas bubble sizes not exceeding 10 microns, said fine bubble sizes being constituted by a mixture of gas bubbles in the range of from 1 to 10 microns, and wherein said first water resistant glass primer cobalt base coat having larger gas bubble sizes than said second glass coating, said first and second coatings being resistant to dissolving at said water temperature of up to about 190 degrees F.