The reservoir tank is used to store water heated by the solar collector.  Once the water in the reservoir is heated, it can then be used to regulate the temperature of the main tank.  The reservoir tank is constructed from a 44 gallon plastic can and is elevated to provide ample gravity feed back to the main tank.
    To heat the reservoir tank, water is pumped out of the tank and into the solar collector, where it is heated to temperatures as high as 120 degrees Fahrenheit.  The water is then gravity fed back into the reservoir tank, where it is stored for later use.
    When the temperature of the main tank drops below an acceptable level, 'cool' water is pumped out of the main tank and into the reservoir tank.  At the same time, the same amount of 'warm' water is gravity fed back into the main tank.  The use of gravity fed systems allows us to easily maintain constant water levels in each of the three main system components.

For plumbing diagrams and more details on the reservoir tank, please see our Online Operation Manual.