BoilerFaultCodesYour boiler is not receiving the correct voltage of electricity, causing it to shut down to protect its internal parts.
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 fault
What causes this fault?
This fault occurs when the main control board detects that the incoming electrical supply has dropped below a safe operating level. The most common reason is a dip in the local power grid or a technical failure within the boiler's internal circuit board that prevents it from processing electricity correctly.
This fault can be more frequent during extreme winter weather or summer storms, when high demand or lightning strikes cause instability in the local electrical grid.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F17 — no call-out fees, no surprises.
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