BoilerFaultCodesYour boiler has detected that a temperature sensor is not attached correctly or has become loose, preventing the system from heating up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Mounting fault sensor S0
What causes this fault?
This fault occurs when the boiler's main flow sensor is not making proper physical contact with the internal pipework. The most common reason is that the metal retaining clip has vibrated loose or snapped, causing the sensor to drift away from the pipe and lose its temperature reading. Without this accurate data, the boiler 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 f014 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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