BoilerFaultCodesYour boiler has detected that its temperature sensors are giving conflicting or incorrect readings, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow and/or return sensor fault: Flow and/or return sensor is faulty (tolerance too great)
What causes this fault?
This fault occurs when the boiler's control board notices that the temperatures reported by the flow and return sensors are too different from one another or are physically impossible. The most common reason is that one of the sensors has degraded and is sending an inaccurate electrical signal, but it can also be caused by a build-up of debris in the pipework affecting the heat transfer.
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 F.72 — no call-out fees, no surprises.
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