BoilerFaultCodes.com
b8 Low

Your boiler has temporarily paused heating because the water inside is already warmer than the temperature you have requested.

Monitor it

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: Control stop: appears if the measured flow temperature (t1) is higher than the flow temperature set (T flow set). The boiler will start working again automatically once the flow temperature falls below the flow temperature set.

DIY fix possible

Check if your room thermostat or boiler temperature dial is set lower than the current water temperature.Ensure your radiators are not all turned off, which can cause heat to build up inside the unit.Wait for the boiler to cool down; it will restart automatically once the internal temperature drops.

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