Legionella infection is a severe form of pneumonia caused by Legionella bacteria. Legionella is common in stagnant water sources such as faucets and shower heads fed directly by a typical household water heater at temperatures between 25°C and 45°C. It is killed at temperatures above 60°C.
A hygiene program in new generation heat pumps from Viessmann helps maintain a high water storage temperature above 60°C for one hour daily or weekly. It should be carried out when there is no hot water demand for bathing or washing to prevent the risk of scald and burns. You can turn this program on in the ViCare app as well as directly on the control panel (display) of your device. In the case of some older heating systems, you can do it manually on the device itself. To do it, open the hamburger menu on the control panel on the left side, choose DHW and hygiene function, and choose the daily or weekly program and preferred time.
Please note: This feature is not available for older-generation heating devices.
If you have been away for an extended period or have not run the hygiene program for some time, you should always flush the lines through which hot water runs (e.g. showers, baths, taps, etc.). This is to ensure that any stagnant water is out of the system. Then run the hygiene program with the water heater set to 60°C or more for at least one hour.