BoilerFaultCodesTechnical description
The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal temperature exceeds safe limits, triggering a safety shutdown to prevent damage. The most common reasons are a lack of water circulation caused by a failing pump, or a faulty sensor that is incorrectly reporting the temperature to the main control board.
This issue often appears when the heating is first turned on after summer, as the pump can seize up after long periods of inactivity.
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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