A solar water heater is a device can be used to capture sunlight in order to heat the water in your pipes to be used for baths, showers.
The water heater absorbs light by means of a collector placed on the roof and converts it into heat. it passes this heat to a water tank by means of a circulating pump. this excanged is triggered by the thermal regulator, but only when the collector is hotter than the water in the collector tank. This prevents the circulating pumps using electricity needlessly. Conversely, it also prevents overheating.