BoilerFaultCodesTechnical description
Flame Loss
What causes this fault?
This fault occurs when the boiler's control system detects that the flame has gone out unexpectedly after it was successfully lit. It is usually caused by a dirty or worn-out sensor that can no longer 'see' the flame, or an inconsistent flow of gas preventing a stable burn. In some cases, external factors like a blocked flue or debris in the burner can also cause the flame to flicker and fail.
This fault is more common during extreme cold spells, as freezing temperatures can cause the external condensate pipe to block, backed-up water then floods the combustion chamber and extinguishes the flame.
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.