Low
S.88 on Vaillant ecoTEC pro 30 H combi A VUW GB 306/5-3

Your boiler is simply running its automatic air-purge routine to clear trapped air from the system, which usually happens right after it has been switched on or refilled.

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 purge programme is activated.

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

DIY fix possible

Wait for a few minutes to let the automatic purge cycle finish and the boiler to return to normal operation.Check your system pressure gauge to ensure it is sitting between 1 and 1.5 bar.If the code does not clear after a while, simply restart the boiler.

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Related fault codes

S.91View →S.30View →F.75View →

All 82 fault codes on the ecoTEC pro 30 H combi A VUW GB 306/5-3

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

F.00F.01F.10F.11F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.83F.84F.85S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.42S.46S.53S.54S.57S.58S.61S.62S.63S.76S.92S.93S.96S.97S.98S.99

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