A02
De Dietrich
Flame Loss During Operation
Boiler attempts to start but shuts down quickly, display shows A02, sometimes with short ignition noise
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
Unstable gas supply pressure, partially blocked burner, faulty ionisation electrode, faulty gas valve modulation coil
How to Fix / Troubleshooting
Safety: Switch off power and close the gas valve before opening the boiler casing. Only a qualified technician should adjust gas settings.
- Reset and observe: Reset the boiler and watch the sequence: fan starts, ignition sparks, flame appears then goes out. Note any unusual noises.
- Check flue and air intake: Ensure the concentric flue terminal is not blocked by leaves, ice, or debris. A restricted flue can cause unstable combustion and flame loss.
- Inspect burner and electrodes: Remove the combustion cover. Clean the burner surface and check for corrosion. Clean and reposition the ionisation electrode so it is well in the flame path.
- Check gas supply stability: Confirm other gas appliances run without fluctuation. If pressure issues are suspected, contact the gas supplier.
- Technician tasks: A heating engineer should check gas valve modulation, measure combustion values (CO₂/O₂) and adjust or replace the gas valve or ionisation electrode if readings are out of range.
Advertisements
Repair Difficulty
Professional Required
5/5
Advertisements