Low
d.25 on Vaillant Home Combi

This is not a fault code, but an information message indicating your boiler is correctly communicating with your controls to keep your hot water at the right temperature.

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

StatusoftherequirementtoreheatthecylinderorforthehotwaterwarmstartfromtheeBUSthermostat

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 32.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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d.24View →d.26View →

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