Low
d.20 on Vaillant ecoFIT Pure 435

Your boiler is displaying the current maximum limit it is allowed to reach when heating your hot water, rather than being a breakdown fault.

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

Maximum hot water set target temperature

DIY fix possible

Check your hot water temperature dial/setting on the front of the boilerAdjust the setting up or down to your preferred temperatureMonitor the display to see if it reverts to the standard temperature reading

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Related fault codes

d.00View →d.01View →

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