BoilerFaultCodesYour boiler has stopped working because its internal computer is receiving conflicting or faulty information from its temperature sensors.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Electronic system or sensor fault
What causes this fault?
This fault occurs when the boiler's main control board detects a logic error between the heat sensors on the flow and return pipes. It usually happens because one sensor is sending a reading that is physically impossible or because the electrical signals are being interrupted by a faulty circuit board.
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 F.64 — no call-out fees, no surprises.
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