Low
S.341 on Vaillant ecoTEC plus Combi

Your boiler is simply taking a short break from running at full power because it has been working hard for a long period, and it will resume normal operation automatically.

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

The unit temporarily decreases the load to the minimum modulation due to long, permanent burner operation.

From this model's manual
Verified against the Vaillant Ecotec Plus 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.

Engineer required

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

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Related fault codes

S.30View →S.31View →

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