BoilerFaultCodesYour boiler is confused because the sensors that monitor the water going in and out are giving conflicting readings.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow/return temperature sensor difference (implausible)
What causes this fault?
This fault occurs when the sensors monitoring the water leaving and returning to the boiler provide contradictory temperature readings, such as the return pipe appearing hotter than the flow. The most common reason is that one sensor has become unclipped or faulty, or the internal wiring has developed a bad connection. It can also happen if the sensors were accidentally swapped during a previous repair.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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