BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler attempts to start but is unable to detect a steady flame, causing it to shut down for safety. The most common reasons include a lack of gas supply to the unit, a build-up of carbon on the ignition probe, or a component failure that prevents the spark from firing.
This fault is more common during extreme cold spells, as external gas regulators or pipes can sometimes freeze, restricting the gas flow required for ignition.
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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