BoilerFaultCodesYour boiler is confused because its internal thermometers are giving conflicting readings and don't agree on how hot the water actually is.
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 permanent deviation
What causes this fault?
This fault occurs when the boiler's internal sensors provide temperature readings that are too far apart for the system to trust, suggesting the water is heating up in a way that doesn't make sense. The most common reason is that one of the sensors has developed a chemical or Electrical fault, but it can also happen if the sensors are incorrectly installed or have become loose from the internal pipework.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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