BoilerFaultCodesTechnical description
Flame loss
What causes this fault?
This fault occurs when the boiler's internal sensor can no longer detect a steady flame after the burner has ignited. The most common reasons include a buildup of carbon on the sensing probe, an inconsistent gas supply, or a component failure that prevents the system from confirming the fire is safely lit.
This fault is more common during extreme cold spells, as freezing temperatures can affect gas pressure or cause the condensate pipe to backup, both of which can extinguish 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.
Find a Gas Safe engineer
Search the official register →