Boiler runs for only a short time then stops; radiators never reach the set temperature.

Safety: No immediate hazard, but efficiency is reduced.

User checks:

• Lower flow temperature: Reduce the heating flow temperature setting to around 60°C and observe if run times increase.
• Open more radiators: Ensure enough radiators are open to absorb boiler output.

Technician actions:

• Check flow and return NTC sensors for accuracy.
• Verify correct pump speed and adjust if necessary.
• Install or adjust an automatic bypass valve if required.
• Review system design versus boiler output and adjust settings (e.g., maximum power) on the Fondital PCB.