BoilerFaultCodesYour boiler is temporarily running at its maximum power level, which is usually a normal setting used by engineers during testing or after a reset.
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: Max. output (heating)
What causes this fault?
This status occurs when the boiler has been manually put into its maximum power mode, often through the service buttons on the front panel. It typically happens after a reset or when an engineer is calibrating the gas valve to ensure the unit can handle peak demand. In most cases, it is not a breakdown but a configuration setting that needs to be toggled off to return to normal operation.
DIY fix possible
Check if the 'reset' button was recently pressed or if the boiler was just turned onWait 5 to 10 minutes for the boiler to complete its startup cycleIf the code persists, try turning the boiler off and on again at the fused spur switch
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