BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal computer detects a major hardware failure or a safety circuit has been triggered, forcing the unit to shut down immediately. The most common reasons include a faulty electronic control board or a malfunction in the ignition system that prevents the gas from lighting safely. It essentially means a critical component is no longer communicating correctly or has failed a safety check.
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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