Low
d.58 on Vaillant ecoFIT Pure 418

Your boiler is notifying you that it is currently using extra heat to warm up your solar water heating system.

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.

What the manual says

Manufacturer manual

Solar circuit reheating

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

No action is required as this is an advisory status message rather than a breakdown.Wait for the reheating cycle to complete automatically.Monitor the display to ensure it returns to normal operation once the cycle finishes.

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