A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications. Overview Application Boilers have many applications. They can be used in stationary applications to provide heat, hot water, or steam for domestic use, or in generators and they can be used in mobile applications to provide steam for locomotion in applications such as trains, ships, and boats. Using a boiler is a way to transfer… (More on Boiler)