BoilerFaultCodesYour boiler has detected a problem with one of its internal temperature sensors and has stopped working as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flashing fast (Sensor Fault)
What causes this fault?
This fault occurs when the boiler's control board loses communication with the temperature sensors or receives a reading that is outside of its safe operating range. The most common reason is that the internal thermistors have physically degraded over time or a wire has shaken loose, preventing the boiler from knowing if the water is becoming dangerously hot.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like FAIL POINT I — no call-out fees, no surprises.
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