BoilerFaultCodesTechnical description
Lockout
What causes this fault?
This fault occurs when the boiler has tried to ignite several times but failed to detect a flame, causing the system to shut down for safety. The most common reasons are a lack of gas reaching the burner, a worn-out ignition spark, or the boiler's internal sensor not recognising that the flame has lit.
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 →