BoilerFaultCodesTechnical description
FLAME LOSS
What causes this fault?
This fault occurs when the boiler successfully lights but the internal sensors fail to detect the flame, causing the system to shut down for safety. The most common reasons are worn-out ignition parts that can no longer 'see' the fire, or an inconsistent gas supply that prevents the flame from staying lit. In some cases, a blocked flue or debris on the burner can also interfere with the combustion process.
This fault is more common in winter, as extremely cold temperatures can cause the gas meter regulator to freeze or 'lock up,' restricting the gas flow needed to maintain a steady 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.
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