BoilerFaultCodesYour boiler has stopped working because one of its internal temperature sensors is providing an incorrect reading or has developed a fault.
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 S3.
What causes this fault?
This fault occurs when the boiler’s internal control system receives an illogical or out-of-range signal from the S3 temperature sensor. The most common reason is that the sensor itself has suffered an electrical failure or the wiring connecting it to the main circuit 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 F030 — 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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