What is a Hot Water Heater?

Water heating is a thermodynamic process using a heating source to heat water above its initial temperature. Potable water is usually heated by a device known as a water heater or hot water system. (Hot water heater is an incorrect, redundant term). Water heaters for nonpotable use, both industrial and domestic, are also called hot water boilers. When a shell-and-tube heat exchanger is used for potable or nonpotable water heating, it is commonly called a hot water generator.