BoilerFaultCodesTechnical description
Low supply voltage
What causes this fault?
This fault occurs when the electrical voltage being supplied to the boiler's control systems drops below a safe working level. The most common reason is an issue with your home's main electrical supply or a failing component inside the boiler, such as the printed circuit board, that can no longer process the incoming power correctly.
This fault can sometimes occur during periods of extreme cold when local power grids are under heavy strain, leading to temporary 'brownouts' or fluctuations in supply voltage.
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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