BoilerFaultCodesYour boiler has detected that one of its internal sensors is frozen or stuck at a specific reading, causing the system 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 stuck lockout
What causes this fault?
This fault occurs when the boiler's internal computer detects that a temperature sensor is providing the exact same reading for too long, suggesting the component has failed or 'frozen'. It usually happens because the internal electrical resistance within the thermistor has broken down, or the wiring connecting it to the main control board has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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