A Simple Principle that Integrates Easily
The solar collectors absorb the sunís rays, convert them to heat and transfer the heat to a heat-transfer fluid. (The heat-transfer fluid is typically a glycol and water mixture in regions where seasonal freezing in a concern.) The heat-transfer fluid is then pumped into a heat exchanger located inside the water storage tank where it heats the water.
After releasing its heat via the heat exchanger, the heat-transfer fluid flows back to the collectors to be reheated. The controller keeps the heat-transfer fluid circulating whenever there is heat available in the solar collectors. In the winter, a boiler serves as an alternate heat source. Solar thermal systems can be integrated into existing hot water systems with relative ease.