BoilerFaultCodesTechnical description
Temporary mis-burning error – could be due to a gas pressure or flue line issue.
What causes this fault?
This fault occurs when the boiler's internal sensor detects that the flame is flickering or unstable rather than burning steadily. The most common reason is a temporary disruption in the balance of gas and air, which prevents the boiler from maintaining a safe and consistent heat output.
This issue can sometimes appear during very windy weather, as strong gusts can occasionally interfere with the air pressure entering the flue pipe.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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