BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler’s safety circuit detects an internal error or overheating, causing it to shut down to prevent damage. The most common reason is a faulty safety thermostat or a breakdown in the communication between the sensors and the main control board. It can also be triggered by damaged wiring preventing the boiler from confirming that all safety systems are functioning correctly.
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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