Low
D.58 on Vaillant Atmomax

Your boiler is currently taking advantage of heat from your solar panels to help warm up your water, which is a normal energy-saving function.

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

Activation of solar reheating

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 fault.Monitor the display to see if the code disappears once solar heating is complete.Continue to use your hot water as normal.

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