To kill the bacteria in the domestic hot water, the water must be heated to 70 °C during a certain time (default = 600 sec).
This protection function is activated if:
We recommend connecting the input "LegionellaEnable" to a time schedule which allows the legionella function to be started by a short pulse.
If the protection function is active, the domestic hot water setpoint will be set to the anti-legionella function setpoint defined by the parameter LEG-01.
The output "LegionellaActive" will be "1" as long as the anti-legionella function is active.
It can be optionally connected to the primary district heat exchanger to increase the return water temperature setpoint.
When both buffer upper and the optional lower water temperature reach the value of the legionella setpoint LEG-01 minus 50 % of the proportional band UWT-01, the function will stop after a time delay defined by parameter LEG-03 "duration legionella".