Low
D.045 on Vaillant ecoTEC plus Combi

Your boiler is signalling that the settings for how hard it should work based on the outside temperature are slightly misaligned, which is usually a configuration issue rather than a broken part.

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

Heatcurveoffset

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 74.
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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Related fault codes

D.044View →D.046View →

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