* Or the solar collector, also known as solar panels, is a method of converting sunlight into heat and storing it for later use to heat water, and by that it saves a large part of the energy allocated to heating water and is considered environmentally friendly so that no chemical is used in it that may harm consumers of water.  It does not produce pollutants that harm the surrounding environment.

 * The solar heater consists of the collector that receives the sun's rays and turns it into thermal energy, and it includes a number of black-coated panels through which metal tubes made of steel or copper pass through them to allow water to pass through them so that they are exposed to the sun's heat for the longest possible period, and the panels are covered with a glass cover  Sealed, the panels connect to a thermally insulated tank that is used to store hot water and supply it to the home when needed.  To transfer the hot water formed in the collector to the isolated tank, one of the following methods can be used:

 * Conveying by load This method depends on the density of the water, in which the isolated tank is above the collector level so that the hot water formed in the collector is allowed to rise from the cold water due to its low density, then the cold water descends to the collector and is heated and rises to the top and this process continues until the temperature is equal.  In all the components of the solar water heater (the water cycle from the collector to the tank, then from the tank to the collector is called the siphon phenomenon).

 * Transfer with the pump In this method, a pump is installed on the cold water line of the isolated tank, and a thermostat controls its operation on the temperature difference between the tank and the collector, so that the pump draws cold water from the tank and pumps it towards the collector to heat it, and the pump is used if the tank cannot be placed  Above the collector level, as if the tank is far from the collector or in the case of large pool heaters used by many consumers.

 * Removal of calcification, which means getting rid of the salts accumulated inside the pipes by filling the tubes with a dilute acid solution, and this is done once or twice annually depending on the quality of the water and the extent of the concentration of dissolved salts in it.  Use a filter if the water soluble salts are high and cause a high degree of calcification.  Repaint the panels with black color in case rust appears.  Ensure that the glass cover on the pipes is tightly closed and that water does not leak, and that rain water does not reach the pipes.