BoilerFaultCodesYour boiler's heating power has been manually limited to a lower setting, which might prevent your home from reaching your desired temperature properly.
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: Maximum heating output: The maximum thermal output can be reduced via the service function 3-b1.
What causes this fault?
This code appears because a settings adjustment has been made to intentionally 'cap' the boiler's maximum power output. It is usually triggered when a technician or user limits the heating capacity to match a smaller property, which can sometimes result in the radiators not getting hot enough during very cold spells. It is not a component failure, but rather a notification that the boiler is not operating at its full potential wattage.
You may only notice this status during winter, as the limited power setting might struggle to keep the house warm when outside temperatures drop significantly.
DIY fix possible
Navigate to the boiler's service menu using the touchscreen or buttons.Locate 'Service Function 3-b1' in the settings.Check if the percentage value is set lower than required and adjust upward if more heat is needed.
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