Danfoss DTW 300 SP, Installation, Service And User Manual

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11.4.9 Restart after long stop
Note! When the system is started again after a long time (trial running included), it is normal that the
outlet water is unclean. Keep tapping out water and it will become clean after some time.
11.5 Legionella prevention
11.5.1 Installation considerations and water temperature setpoint
The output water temperature setpoint is recommended to be set so that the temperature at the customer con-
sumption output is above 50°C. The reason is to prevent legionella in pipes and joints. Also, national rules may
exist that set requirements for this condition.
When installing the product, the installer must pay attention to this issue and adjust the water temperature set-
point of the application accordingly.
11.5.2 Automatic legionella prevention heat-up function
There is an automatic legionella protection function in the product control system. Once the user turns on the
mains supply to the unit (which makes the pcb timer to start calculating) or resets the time of the unit, the unit will
heat up the water up to 65°C on the next day at 23:00. This kills any possible legionella bacterias in the water inside
the storage tank. This function will be repeated on a weekly basis, so after 7 days, the unit will heat up the water to
65 °C again, and so on.
32 – Installation, Service and User Manual VMGFK202