What is important to know about the Solar Hot Water Tank?



The solar hot water tank is one of the two major parts of the solar heater system.

for overview of solar hot water heaters click here

The solar tank is a reservoir for hot water, connected to the cold water home supply, to the hot water pipe that goes to the home usage and to the collector . A loop of pipes connect the tank to the solar collector

solar hot water tank

In mild climate areas it is water that flows from the tank to the collector and return to the tank hotter. This cycle is repeated until the water reaches the preset temperature.

In colder climate areas, where freezing conditions might occur, the loop flows anti freeze fluid (such as glycol) and not water. If this is the case, the tank is also equipped with a heat exchange that transfers the heat to the water stored in the tank.


The tank is foam insulated to avoid heat run away and saving on heat energy losses.

What parts will you find inside the tank or attached to it?

  • An anode rod for corrosion protection
  • Temperature and Pressure Relief Valves
  • 4 Water Connections
  • A Heating Element and Automatic Thermostat ( for the back-up system)

If anti freeze fluid is used than the following are also added.

  • Heat exchange
  • An Optional Automatic Temperature Control

Helpful hints

  • Insulate the pipes to avoid thermal losses
  • Use the shortest possible hot water pipes
  • Use a filter on the cold water inlet to prevent the deposit of debris and to prevent the build up of scale


Standard tank sizes

Choose the right size according to your family size. The following are the standard sizes you will find.

  • 60 gallons
  • 80 gallons
  • 120 gallons

more on sizing the solar hot water tank

click here to view the solar heater types page

click here to return to home page