BoilerFaultCodesTechnical description
Temporary fault code (Refer to section 7.10)
What causes this fault?
This fault occurs when the boiler's internal sensors detect an inconsistent temperature reading or a slow rate of water flow through the system. This is often caused by a buildup of debris or lime scale within the heat exchanger, or a sensor that is starting to fail and providing inaccurate data. Much like a safety check, the boiler pauses briefly to ensure it doesn't overheat before attempting to fire up again.
DIY fix possible
Check if the boiler display resets itself automatically after a short periodPress the reset button or turn the mode selector switch to 'OFF/RESET' and then back to heating/hot waterEnsure your system pressure is topped up to between 1 and 1.5 bar on the pressure gauge
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