BoilerFaultCodesYour boiler has detected an electrical fault with its internal temperature sensors and has stopped running as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: HP flow sensor short / HP return sensor short
What causes this fault?
This fault occurs when the boiler's control board receives an impossible electrical signal from the sensors that monitor the water temperature. The most common reason is that the internal wiring or the sensors themselves have developed a short circuit, often due to natural wear or moisture ingress. Because the boiler can no longer safely monitor how hot the water is getting, it shuts down immediately to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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