Low
S.97 on Vaillant ecoTEC exclusive 835 VUW 356/5-7

Your boiler is currently running a brief self-test on its water pressure system and temporarily pausing heating until the check is complete.

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 test running, heating demands are blocked.

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Exclusive 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 for the boiler to complete its automated test cycle.Check the digital display to see if the code clears itself or changes to a different message.If the code persists for more than 15 minutes, try restarting the boiler.

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Related fault codes

F.22View →S.30View →S.41View →

All 207 fault codes on the ecoTEC exclusive 835 VUW 356/5-7

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

conF.00F.00F.01F.01F.02F.02F.03F.03F.10F.10F.11F.11F.12F.12F.13F.13F.20F.20F.22F.22F.23F.23F.24F.24F.25F.25F.26F.26F.27F.27F.28F.28F.29F.29F.32F.32F.33F.33F.35F.35F.42F.42F.49F.49F.55F.55F.56F.56F.57F.57F.61F.61F.62F.62F.63F.63F.64F.64F.65F.65F.67F.67F.68F.68F.70F.70F.71F.71F.72F.72F.73F.73F.74F.74F.75F.75F.77F.77F.78F.78F.80F.80F.81F.81F.82F.82F.83F.83F.84F.84F.85F.85F.90F.90F.94F.94P.00P.01P.02P.04P.06P.14S.00S.01S.2S.02S.3S.03S.04S.05S.06S.07S.08S.09S.09S.10S.10S.11S.11S.13S.13S.14S.14S.15S.15S.16S.16S.17S.17S.19S.19S.20S.20S.21S.21S.22S.22S.23S.23S.24S.24S.25S.25S.26S.26S.27S.27S.28S.28S.29S.29S.30S.30S.31S.31S.32S.32S.33S.33S.34S.34S.36S.36S.37S.37S.39S.39S.40S.40S.41S.41S.42S.42S.46S.46S.53S.53S.54S.54S.55S.55S.56S.56S.57S.57S.58S.58S.59S.59S.76S.76S.86S.86S.88S.88S.92S.92S.93S.93S.96S.96S.98S.98S.99S.99

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