BoilerFaultCodesTechnical description
Mains voltage too low
What causes this fault?
This fault occurs when the electrical supply entering the boiler drops below the minimum threshold required for the internal components to function. It is usually triggered by a temporary dip in the local power grid, though it can also be caused by loose internal wiring or a failing electronic control board within the unit.
This issue is more frequent during winter or periods of extreme weather when the local electrical grid is under heavy load or damaged by storms.
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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