BoilerFaultCodesYour boiler has stopped working because its internal temperature sensor has developed an electrical fault and can no longer safely monitor the heat level.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked - Boiler temperature sensor shorted out
What causes this fault?
This fault occurs when the electrical connection inside the boiler's main temperature sensor fails, causing it to send an incorrect signal to the control board. The most common reason is internal wear or a moisture leak that has damaged the sensor's wiring, making it impossible for the system to safely monitor the water temperature.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 30 — no call-out fees, no surprises.
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