BoilerFaultCodesYour boiler's internal computer has lost power or suffered a hardware failure, meaning it cannot control the heating or hot water functions.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Defective control panel or blown F3 fuse.
What causes this fault?
This fault occurs when the boiler's main control board loses electrical power or suffers an internal hardware failure. The most common reason is a blown fuse on the board caused by an electrical surge, though it can also happen if the circuit board itself has simply worn out and can no longer process commands.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 7F — no call-out fees, no surprises.
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