I have realized now why the relay used to monitor my Heat Pump, and why the smart plugs I am using to monitor the consumption of my Mill heaters, keep on switching on and off.
Because I have classified these devices as "heaters" in order for their measured power consumption to be shown as "heat" in the energy statistics.
However this means that by default AND without explicitely saying it to the user, FH steers these smart plugs/relays as if they were real heaters to be controlled by the room temperature measured elsewhere/by another device! So FH keeps on sending commands to switch these off while their built-in Auto ON keep on pushing them back on all the time.
Users should be allowed to choose whether individual "heating" devices are to be controlled by FH together with the other ones present in the room.
OR allow users to choose under what consumption category the power consumption is to be reported!! To avoid the FH "heater" algorithm to mess up with my plugs and relays I have to classify them as Lighting or Appliances etc, that's absurd!