BoilerFaultCodesTechnical description
Burner fault. Mains voltage is too low. Check the power supply.
What causes this fault?
This fault occurs when the boiler's internal computer detects that the incoming electricity supply has dropped below a safe working level. The most common reason is a problem with your home's electrical circuit or a failing component on the boiler's main control board that can no longer process power correctly.
This issue can occasionally trigger during peak winter months if the local electrical grid is under heavy strain or during stormy weather that causes fluctuations in power stability.
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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