As the name suggests the water heater 's function is to provide hot water. Tank water heaters and the tankless water heater are the most widely used types of this heater. The design or structure of the water heater is that the entire heater is sealed, and two pipes are arranged in parallel. A gas burner at the bottom is present perpendicular to both of these tubing. Hot water is entered through one of the pipes and the burner heats the incoming hot water at the bottom of the heater and then the warm hot water rises up and then is transferred to different parts of the same house, such as the toilets, tabs, tubs, sinks, levorotary etc. The pipe for cold water entry is wide and cold water quickly reaches it but the pipe for hot water evaporation is thin so that only the hot steam or water evaporates into a small pipe.

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