BoilerFaultCodesTechnical description
Light indication during fault not covered by other details. Control board likely wet, damaged, or malfunctioning.
What causes this fault?
This fault usually happens if the boiler was accidentally left in a special diagnostic mode after a service, which prevents it from operating normally. It can also occur if the boiler's internal computer loses control over the hot water temperature, often due to a faulty sensor or a sticking gas valve. Essentially, the system has detected that it cannot safely regulate the heat and has shut down to protect itself.
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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