BoilerFaultCodesYour boiler has detected that the electrical supply coming into the unit is currently too low for it to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Power supply <170 V
What causes this fault?
This fault occurs when the electrical voltage entering the boiler drops below a safe threshold, meaning there is not enough power for the internal components to function. Typically, this is caused by a problem with your home's main electricity supply or a failing electronic control board within the boiler itself. In some cases, it can also be triggered by a loose or damaged power cable that is preventing a steady flow of electricity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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