Low
d.36 on Vaillant Home System

Your boiler is simply displaying the current speed of your hot water flow as an informational check rather than reporting a breakdown.

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

Value for the hot water flow: Current value in l/min

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

Press the 'Menu' or 'Back' button to exit the diagnostic modeTurn off any running hot water taps to see if the value changes to zeroRestart the boiler if the display remains stuck on this information screen

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Related fault codes

d.35View →d.40View →S.14View →

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