BoilerFaultCodesTechnical description
Final fault code (Refer to section 7.11)
What causes this fault?
This fault occurs when the boiler's internal temperature exceeds a safe limit, causing the system to shut down to prevent damage. The most common reasons are a failed pump stopping water from circulating or a build-up of air and debris creating a blockage within the heat exchanger. It can also be triggered by 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 internal pump can seize up during 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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