BoilerFaultCodesYour boiler has detected a fault with its internal temperature sensor, meaning it cannot safely measure the heat of the water and has stopped working as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: S1 sensor short circuit
What causes this fault?
This fault occurs when the boiler's control board loses its connection to the flow temperature sensor or receives an incorrect electrical signal. Most commonly, this is caused by the internal sensor failing due to age or the electrical wiring becoming damaged or loose. Because the boiler no longer knows how hot the water is, it shuts down to prevent the system from dangerously 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 F01 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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