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FCU - Default application - Problem with fan control

Issue

The default application does not work correctly.

Possible cause and solution

Fan control despite logic indicating no demand

As depicted below, with FCU Mode set to Heating and the Occupied mode enabled, the Setpoint is lower than CV, indicating no heating demand. Despite this, the fan is controlled at 96.67%.

facncontrol.png

Solution

In the Fan_Control component, the Heating Occupied Active slot is set to true. This configuration causes the fan to turn on in the heating mode even though there is no demand. To solve this problem, set the value of the Heating Occupied Active slot to false.