E63, E65, E69 — Combustion level out of range

What does E63, E65, E69 mean?

The boiler's combustion levels are outside the acceptable range, which can affect efficiency and safety. This might be related to fan speed or flame signal correction.

• Flue gas recirculation (exhaust gases being drawn back into the combustion air intake).
• Issues with the burner or gas supply affecting combustion.
• Faulty components involved in combustion analysis.

Click steps to track your progress.

1. 1

   Turn off the main power supply to the boiler, wait 30 seconds, then turn it back on.

2. 2

   Ensure the boiler's flue terminal outside is clear of any obstructions and not too close to other air intakes.

3. 3

   A qualified technician should perform a combustion analysis and check for flue recirculation.