Low
d.04 on Vaillant Home System

Your boiler is currently displaying the live temperature of the water inside your hot water storage cylinder.

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

Water temperature in the cylinder: Current value

From this model's manual
Verified against the Vaillant Home System installation & service 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 information code, not a fault.Press the 'Back' or 'Menu' button to return to the main display if you have finished viewing the temperature.

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