Low
SEr on Vaillant ecoTEC exclusive

Your boiler is simply reminding you that it is time for its scheduled annual safety check and service.

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

Maintenance indicator: service signal shown alternately with the current pressure after expiry of the set number of burner operating hours.

Shared across the ecoTEC exclusive range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 71 fault codes on the ecoTEC exclusive

Seeing a different code? Every code this model can display, in one place.

conF.0F.1F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.70F.71F.72F.73F.74F.75F.76F.77P.0P.1P.2P.5P.6S.0S.1S.2S.3S.4S.5S.6S.7S.8S.10S.11S.13S.14S.15S.16S.17S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.36S.41S.42S.53S.54S.96S.97S.98

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