The Working of solar water heating system is based on the principles of black body heat absorption & Heat Transfer. The black surface of the collector absorbs the heat from the solar radiation and transfers it to the water passing through the copper tubes (risers) of the absorber panel. Hot water being lighter than the cold water rises to the top of the collector and into the hot water tank. This cycle goes on during hours of sunshine (usually between 10am to 4pm). At the end of the day the tank is full of hot water at designed temperature.

Cold water from cold water tank is pumped into the battery of collectors. The Solenoid valve/pump On/Off operation is controlled by PT - 100 sensor installed at the last collector of the one after row of the system. As the system in designed for X degrees the solenoid valve/pump is activated as soon as the temperature in the solar collector attains X degrees. The solenoid valve/ Pump will remain ON till all the hot water is replaced by cold water.

This cycle continuous throughout the day, i.e. during the period of sunshine till the tank is full which is controlled by Liquid Level Controller. The frequency of solenoid valve/pump operating cycle depends on the intensity of solar radiation during sunshine hours and this frequency of the cycle is maximum during peak period. During rainy seasons / non sunny days the time of each solenoid valve/pump operating cycle could be more depending upon the intensity of solar radiation.

This system id designed to deliver designed liters per day at designed degree centigrade. The hot water storage tank gets filled up by the end of the day. Once the maximum level is reached in the tank, the LLC sensor provided in the tank level tube stops the operation of the solenoid valve/pump. Further the solenoid valve/pump operation will only start when the level of water goes below the maximum level mark in the hot water tank & temperature in solar panel is designed degree's and above. The necessary indications of each solenoid valve/pump on , mains on , temperature reached, water level in the tank are provided at suitable places on the panel box.

The whole system is controlled and synchronized through the control panel provided to the system.

Please note that the solar system is designed on the metrological data available in solar radiation data book for that district, for specific capacity and temperature, depending upon the hot water consumption pattern for the day and must be utilized accordingly. The designed output of the system may vary according to change in climatic condition during the year.