Low Warning
59:1 to 59:10 on Viessmann Vitodens 300-W

Your boiler is notifying you of an adjustable temperature setting related to the DHW cylinder pump, which is usually a configuration advisory rather than a mechanical failure.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Starting point adjustable from 1 to 10K below the set value

What causes this fault?

This fault occurs when the boiler's control system identifies a mismatch in its internal operational settings, specifically regarding the temperature drop allowed before it fires up again. It is typically caused by a minor electronic glitch within the main control board or a slight calibration error in the temperature sensors. While the boiler continues to function, it is highlighting that its internal logic for managing heat cycles is slightly out of sync.

DIY fix possible

Press the 'Reset' button on the control panelTurn the boiler off and back on at the fused spur switchMonitor the display to see if the code clears after a restart

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