It is not enough for us that only the drinking water is healthy, but also the water that reaches every tap in the house, we want it not to be a carrier for dangerous infectious diseases (eg legionnaires’ disease, etc.). Water can also be contaminated in the home during storage and circulation for consumption, either by accident or by distribution conditions.

These risks are limited by the design of the facilities in order to achieve:

  • to avoid stagnation
  • short connection lines
  • the main consumer at the end of the single connection line
  • separation of parts that are not used
  • proper dimensioning
  • to avoid heating cold water (max. 25 ° C) 
  • to avoid cooling hot water(min. 55 ° C).

Water storage

Plastic, metal or concrete tanks can be found in almost every home.

In storage tanks, water can be contaminated by the entry of foreign substances from the collection system or openings (lids, overflow, ventilation, etc.). Prolonged exposure to high temperatures promotes the multiplication of germs. Keeping water cool is a basic rule of hygiene. Water renewal and the periodic or controlled addition of disinfectants are necessary.

Network design


Water stagnation in piping sections that are not used often guarantees the risk of microbial growth. Many companies, such as Rehau, offer special design of networks with special components, so that the water does not remain stagnant. Each time a faucet is opened, the entire contents of the pipe are set in motion, thus rinsing each point and there is no risk of germs forming in the system.

Thermal disinfection with heat shock

The healthiest way to kill bacteria is to raise the temperature of the water.

In hot water networks, which are dangerous for the growth of infectious microorganisms (such as legionella), the application of a periodic increase of the water temperature for the extermination of any growing colonies is foreseen. This periodic increase must be made by recirculating the entire hot water distribution network and not just in the boiler.

Temperature adjustment


The high temperatures in the boilers require the control of the temperature of the hot water that circulates, in order to have in our tap the temperature of the water we need, to avoid dangerous burns, but also to reduce the heat losses.

Special automatic mixing valves ensure the desired temperature of hot water.