BoilerFaultCodesYour boiler is confused because the temperature sensors measuring water going out and coming back are giving contradictory or swapped readings.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault: NTC temp. diff. implausible Temperature difference is implausible. Check: Flow/return temperature sensor (correct thermal connection, sensors are inverted).
What causes this fault?
This fault occurs when the boiler's internal computer notices that the temperature sensors for the water leaving and returning to the unit are giving conflicting or 'impossible' data. The most common reason is that the sensors have been clipped onto the wrong pipes during a repair, or a sensor has become loose and is no longer reading the temperature correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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