How Does Solar Water Heater Work 

  How Does A Tankless Water Heater Work

  Tankless water heaters heat water directly without the use of a storage tank. Therefore, they avoid the standby heat losses associated with storage water heaters.

  When a hot water tap is turned on, cold water travels through a pipe into the unit. Either a gas burner or an electric element heats the water.  Following is an example of gas tankless.

  Tankless water heaters deliver endless and  constant supply of hot water on demand whenever you need. You don't need to wait for a storage tank to fill up with enough hot water.