A water heater adds heat to water, raising its temperature. A commercial gas water heater consists of a gas fired burner to heat the water, and a separate hot water storage tank. In most residential water heaters, the heater is combined with the storage tank. A commercial gas water heater also differs from a residential water heater in capacity and durability or life expectancy, and in the fact that there can be multiple heaters and multiple tanks.

This topic covers information related to plumbing equipment that is installed during construction. Plumbing equipment is a component of the building that provides a specific service to the plumbing system. Plumbing equipment may include water softeners, water filtration equipment, electric or fuel fired water heater(s) and water heater exchangers.

This topic includes information related to water softeners that are installed during construction. Water softeners are installed inline with water supply piping in residential and commercial structures. They soften water, reducing the dissolved minerals commonly found in hard water.

This topic includes information related to water filtration systems installed during construction. Water filtration systems purify water, removing any impurities through a barrier, chemical or biological process. They are commonly used for irrigation, swimming pools, manufacturing or inline with supply piping that provides drinking water.

This topic includes information related to electric water heaters that are installed during construction. Electric water heaters heat water to a desirable temperature using electricity as an energy source. Electric water heaters can be a tankless, instantaneous appliance, or a hot water tank rated for residential, light commercial or commercial use.

This topic includes information related to instantaneous electric water heaters that are installed during construction. Instantaneous electric water heaters are stand-alone appliances that heat hot water upon demand of the end user. They are tankless systems that are also known as on demand water heaters.

This topic includes information related to fuel fired water heaters that are installed during construction. Fuel-fired water heaters heat water to a desirable temperature, using natural gas, propane or heating oil as an energy source. Fuel-fired water heaters can be a tankless, instantaneous appliance, or a hot water tank rated for residential or commercial use.

This topic includes information related to water heat exchangers that are installed during construction. Water heat exchangers are devices that are manufactured to efficiently transfer heat from one source to another. They may be instantaneous, circulating, non-circulating, brazed-plate, frame and plate or a reclaimers.