electric water-heater tank 
Mechanism cutting off the flow of electric current when the temperature of the water exceeds a set value.
Pipe through which water escapes when maximum pressure is exceeded.
pressure relief valve
Device for lowering the pressure inside the tank by releasing excess hot water.
Device for emptying water from the tank.
Point where the hot-water tank connects with the household circuit.
Device that senses changes in temperature and automatically switches the upper heating element on or off.
Outlet pipe for hot water flowing into the hot-water circuit.
Inlet pipe for cold water to the tank.