It's method of operation is relatively simple: Heat is generated in collectors warmed by the sun and transferred to a hot water storage cylinder using a circulating fluid thereby heating the water in the cylinder. All the energy collected is stored and is available for use when required. Direct sunlight is not required. Panels work on overcast days.

It can be used where ever heated water is required. This is mainly domestic and commercial hot water, but can also be used for process heat, and heating swimming pools.

How does the system know when to run?

The system has a differential temperature controller. Using a sensor in the collector and another at the bottom of the hot water cylinder, it measures the difference between the two. As soon as the collector is 6degC warmer than the bottom of the tank, a circulating pump is switched on to transfer heat to the cylinder. This differential is chosen as it ensures more energy is transferred to the cylinder than is used by the pump. The pump will continue to run until the temperature differential falls to 4degC or the tank is completely heated to a preset temperature.

What happens when the solar collector does not completely heat the cylinder?

On days where there is insufficient solar gain either due to very poor weather or the changing seasons, your backup source of energy – your boiler or immersion element, will top up the temperature of the cylinder to the required level.