BoilerFaultCodesYour boiler has detected an internal electrical glitch or a faulty temperature sensor, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor or electronics fault | Check NTC's/connections or electronics defect
What causes this fault?
This fault occurs when the boiler's control system receives conflicting or impossible signals from its internal temperature sensors. The most common reason is an electrical short-circuit or a broken connection within the sensors themselves, which prevents the boiler from safely monitoring how hot the water is getting.
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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