BoilerFaultCodesTechnical description
Under voltage.
What causes this fault?
This fault occurs when the electrical supply reaching the boiler's control centre drops below the minimum level required to operate the internal electronics. The most common reason is a malfunction within the main circuit board itself or a loose wiring connection that is preventing a steady flow of power. In some cases, it can also be triggered by a temporary drop in the mains electricity supply coming into your home.
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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