BoilerFaultCodesTechnical description
Supply voltage is below low limit
What causes this fault?
This fault occurs when the electrical supply entering your boiler drops below the minimum level required for its internal components to function correctly. It is often caused by instability in the local power grid, a faulty electrical connection within your home, or a failing internal control board that can no longer process the incoming voltage.
This issue can be more frequent during periods of extreme cold or heatwaves when the national grid is under heavy load, potentially causing 'brownouts' or voltage fluctuations in residential areas.
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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