Low
S.27 on Vaillant ecoTEC pro 28

Your boiler is undergoing a standard cooling cycle to move leftover heat away from the system, and this is a normal part of its operation.

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

Pump over run

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 05 2006 installation & service manual, page 43.
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.28View →S.30View →

All 135 fault codes on the ecoTEC pro 28

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

3596conConnectionD,11D.0D.1D.2D.3D.4D.5D.7D.8D.9D.10D.12D.13D.17D.18D.20D.22D.23D.25D.27D.28D.30D.33D.34D.35D.40D.41D.44D.47D.50D.51D.60D.61D.64D.65D.67D.68D.69D.70D.71D.72D.75D.76D.77D.78D.80D.81D.82D.83D.84D.90D.91D.93D.96D.97F.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.77F.78F70P.0P.1P.2P.3P.4P.5P.6S. 2S. 5S.0S.1S.3S.4S.6S.7S.8S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.28S.30S.31S.32S.34S.36S.41S.42S.52S.53S.54S.96S.97S.98

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