BoilerFaultCodesYour boiler has noticed that its two internal temperature sensors are giving conflicting readings, suggesting they are either broken or have been installed incorrectly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Error with flow/return temperature sensor temperature changing error
What causes this fault?
This fault occurs when the boiler's control board detects that the flow and return temperature sensors are reporting contradictory data, such as the return pipe being hotter than the flow pipe. The most common reason is that the sensors have been clipped onto the wrong pipes during a repair, or the internal sensors have developed a chemical fault and are sending incorrect electrical signals.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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