The Free Flow Series is a thermosyphon system. As a self contained solar water heating system, the Free Flow Systems have collector(s) positioned lower than the tank(s) and operate on the principle of natural convection.
As the sun heats the water in the collector, it expands slightly and becomes lighter, causing the water to rise into the tank in the same way that a balloon rises in the air. The colder, heavier, water in the tank then sinks into the collector. These events create a continuous natural circulation.
Thermosyphon systems are widely accepted throughout the world today. They are automatic, simple, and reliable.
Thermosyphon Systems do not require a pump or control.
There are no moving parts which allows for minimal, if any, maintenance concerns.