BoilerFaultCodesTechnical description
Internal fault (Reset required)
What causes this fault?
A solid red light indicates that the boiler's internal safety system has detected a generic malfunction, preventing it from firing up. This is often caused by a failure in the ignition process or a breakdown in communication between the main control board and vital components like the gas valve. While a simple reset may temporarily clear it, the fault usually points to a failing part that is no longer operating within safe limits.
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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