Low
S.88 on Vaillant ecoTEC plus 938 VUI 286/5-5 R6

Your boiler is currently running an automatic program to clear air bubbles out of the internal pipework and does not require a repair.

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

Purging programme is running

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus 938 Vui 286 5 5 Isim 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 approximately 5 to 10 minutes for the purge cycle to finish automatically.Ensure all radiator valves are open to help move air through the system.Check that the boiler pressure is between 1.0 and 1.5 bar on the display.

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Related fault codes

S.0View →F.22View →F.24View →

All 59 fault codes on the ecoTEC plus 938 VUI 286/5-5 R6

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

F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.42F.49F.52F.53F.54F.55F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.80F.81F.82F.83F.84F.85F.90F.91F.92F.93F.94S.92S.93S.96S.97S.98S.99

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