Low
d.40 on Vaillant ecoFIT pure

Your boiler is displaying the current temperature of the water heading out to your radiators and is not an error code.

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

Heating flow temperature

DIY fix possible

No action is required as this is a status message rather than a faultPress the 'back' or 'menu' button to return to the main display if neededMonitor the temperature reading to ensure it reaches your set thermostat target

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