The main components of scale are calcium carbonate, basic magnesium carbonate and magnesium hydroxide. It is not recommended to use strong acids such as hydrochloric acid, which may damage the metal parts and seals of solar energy. Weak acids such as acetic acid or citric acid can be used, and their calcium and magnesium salts are soluble in water, which not only removes the scale, but also does not damage the solar energy, even if it is not cleaned, it will not harm the human body.