Display shows '04' — Flow temperature higher than set

What does 04 mean?

This message indicates that the actual flow temperature within the heating system has exceeded the upper limit value you previously set. Although listed as a normal operation message, it may suggest the system is overshooting the target temperature.

• Space heating water temperature knob set too low or in an unintended range
• Room controller (e.g. RC35) settings causing a higher demand than desired
• External factors causing heat input not accounted for by the boiler

Click steps to track your progress.

1. 1

   Check the 'space heating water temperature' rotary knob (pos. 5) on the BC10 controller.

2. 2

   Adjust the knob to the desired upper limit value for heating operation.

3. 3

   If a room thermostat is connected, verify its settings and ensure they align with your heating preferences.

4. 4

   If the issue persists or you cannot adjust the temperature, contact a qualified service technician.