Boiler feed water should be free of hardness. Sometimes, due to the short or improper operation of the hardness device or the failure to regenerate the resins in time, some hardness enters the boiler feed water. Increasing the water temperature in the boiler reduces the solubility of water solutes. The water near the hot surfaces becomes saturated and the conditions for deposition of less soluble substances are provided and eventually sediment is formed.

Water hardness is caused almost entirely by calcium and magnesium ions. Other divalent and trivalent metals have a similar effect, but are not usually present in sufficient concentrations in drinking water to cause problems. High hardness prevents the formation of soap scum and can cause scale in water systems, especially boilers, cooling systems, and fresh water piping.

This term is the name of advanced products with scale removal, anti-scale and anti-corrosion properties that are designed to help optimize energy consumption and solve scale and corrosion problems in industrial water systems. The name "Mitreh" is derived from the ancient word "Mitreh" which means pact, friendship and sun. This name reflects the commitment of the creators of Mitreh to create a friendly relationship between industry and water.

Hard water is a term used to describe water containing cations of calcium, magnesium, strontium, iron, manganese, etc. Since the amount of strontium, iron, and manganese in water is very low, calcium and magnesium cations are considered the main cause of water hardness.