BoilerFaultCodesYour boiler has detected a temporary internal communication or sensor error that may resolve itself or lead to a full lockout.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Temporary fault code (Refer to section 7.10)
What causes this fault?
This fault occurs when the boiler's internal computer receives an inconsistent or 'out-of-range' signal from one of its sensors. It is usually caused by a failing temperature sensor or a loose connection in the wiring harness that briefly interrupts the data flow. While the boiler may try to continue operating, it tracks these errors as a sign that a component is nearing the end of its life.
DIY fix possible
Turn the mode selector switch to the 'OFF/RESET' position.Wait for 30 seconds.Turn the switch back to the 'ON' or 'HOT WATER' position and see if the code clears.
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