Low
S.97 on Vaillant ecoTEC plus 938 VUI 286/5-5 R6

Your boiler is currently running a routine internal check on its water pressure sensor to ensure it is working correctly.

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

Water pressure sensor self-test

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 a few minutes to see if the status code clears itself once the self-test finishes.If the code remains or locks out the boiler, try a simple soft reset using the power button.

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Related fault codes

F.22View →S.30View →S.40View →

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.88S.92S.93S.96S.98S.99

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