BoilerFaultCodesYour boiler has stopped working because an internal temperature sensor is reporting an error and needs to be checked.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor S0 is defective.
What causes this fault?
This fault occurs when the boiler's main internal temperature sensor fails to send a consistent electrical signal back to the central control board. The most common reason is that the sensor has suffered a physical failure or the wiring connecting it has become loose or damaged over time. Because the boiler can no longer accurately monitor how hot the water is, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F000 — no call-out fees, no surprises.
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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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