BoilerFaultCodesYour boiler has detected a problem with its internal temperature sensors, which means it cannot accurately monitor the water temperature and has stopped working 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 fault S2
What causes this fault?
This fault occurs when the boiler’s return sensor, which monitors the temperature of the water coming back from your radiators, sends an incorrect or missing signal to the main computer. The most common reason is that the sensor itself has developed an electrical internal failure, or the wiring connecting it to the 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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A boiler cover plan would cover faults like 24 — 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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