Hot Water Tank Drain Valve

drain valve
Device designed to allow drainage of stored contents from a water heater.
A plastic or brass valve located near the bottom of the water heater that allows the tank to be drained when the water heater needs to be replaced and also permits periodic partial draining by the homeowner to flush out sediments that may have accumulated in the bottom of the tank.
A valve located at the bottom of a spill container to drain accumulated liquid into the UST.  Drain valves, depending on the type, may be activated by pulling a chain, pushing a rod, or pulling a lever.

water tank
cistern: a tank that holds the water used to flush a toilet
A tank supplying water for water-based fire protection systems.
Water tanks are liquid storage containers, these tanks are usually storing water for human consumption. The need for water tank systems is as old as civilized man.

hot
Feeling or producing an uncomfortable sensation of heat
Having a high degree of heat or a high temperature
(of food or drink) Prepared by heating and served without cooling
used of physical heat; having a high or higher than desirable temperature or giving off heat or feeling or causing a sensation of heat or burning; "hot stove"; "hot water"; "a hot August day"; "a hot stuffy room"; "she's hot and tired"; "a hot forehead"
characterized by violent and forceful activity or movement; very intense; "the fighting became hot and heavy"; "a hot engagement"; "a raging battle"; "the river became a raging torrent"
extended meanings; especially of psychological heat; marked by intensity or vehemence especially of passion or enthusiasm; "a hot temper"; "a hot topic"; "a hot new book"; "a hot love affair"; "a hot argument"