Normally non pressurised systems are working up to 0.8 Kg / Cm2 , The storage tank is placed at a certain height relative to the top of the collector to prevent the reverse circulation during off-sun shine hours. In this system, hot water storage tank can be under normal pressure of cold water overhead tank so gravitational force of overhead cold water tank comes to bottom of hot water tank at normal pressure ( non pressurized), hot water comes out from top of hot water solar tank and release at the end of tap as a regular.

Normally non pressurised systems are working up to 0.8 Kg / Cm2 , The storage tank is placed at a certain height relative to the top of the collector to prevent the reverse circulation during off-sun shine hours. In this system, hot water storage tank can be under normal pressure of cold water overhead tank so gravitational force of overhead cold water tank comes to bottom of hot water tank at normal pressure ( non pressurized), hot water comes out from top of hot water solar tank and release at the end of tap as a regular.