BoilerFaultCodesTechnical description
Under voltage
What causes this fault?
This fault occurs when the electrical voltage being supplied to the boiler drops below the minimum level required for the internal components to function. Typically, this is caused by a problem with the mains electricity coming into the property or a loose connection within the boiler's internal wiring. In some cases, it can also be triggered by a failing printed circuit board that can no longer process the incoming power correctly.
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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