Closely coupled systems are the solar water heating systems where both the tank (geyser) and solar collector are on the building’s roof. The tank is typically mounted horizontally above the solar collector. In some instances, the solar collector and tank are integrated to form one structure.

The water in a closely coupled system is heated by the solar collector and circulated into the tank using a principle called thermo-siphon. In short, thermo-siphon uses the property where hot water rises and cold water sinks.

Split Systems

Split solar water heating systems allow for the tank to be placed inside the roof – improving the aesthetics of the solution. Split solar water heating systems either use thermo-siphon or pumping to circulate the water within the solar water heating system.