BoilerFaultCodesYour boiler has stopped working because one of its internal heat sensors has developed a fault and can no longer read the temperature correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: S2 sensor short circuit
What causes this fault?
This fault occurs when the boiler's control system detects that the S2 temperature sensor has developed an electrical short circuit, meaning it can no longer safely track the heat level. The most common reason is that the sensor's internal components have failed due to age or heat stress, or moisture has compromised the electrical connections. Because the boiler doesn't know the exact temperature of the water, 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 F02 — 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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