A11
Beretta Flue Overheat Lockout

Boiler displays A11, burner stops, fan may continue to run, possible smell of overheating from flue area.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Severely restricted flue, Incorrect flue length or configuration, Failed flue overheat thermostat, Fan not providing adequate extraction

How to Fix / Troubleshooting

Safety: Turn off the boiler and do not use it until the flue system has been checked. Risk of flue gas spillage.

  • Visual external check: Confirm the flue terminal is unobstructed and correctly positioned according to local regulations.
  • Technician – flue inspection: A qualified engineer should inspect the entire flue run for blockages, collapsed sections, or incorrect slopes.
  • Technician – test flue thermostat: Check continuity and operation temperature of the Beretta flue overheat thermostat. Replace if it trips at too low a temperature.
  • Fan performance: Verify fan speed and pressure. Replace the fan if it cannot maintain proper extraction.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Flue Overheat Thermostat
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements