Low
S.97 on Vaillant ecoTEC plus

Your boiler is currently performing an internal health check on its sensors and has temporarily paused heating and hot water to ensure everything is functioning safely.

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.

Technical description

Automatic test programme: Water pressure sensor, heating and hot water request blocked.

DIY fix possible

Wait up to 15 minutes for the automatic sensor test to finishCheck the boiler's display for any further error codes once the test endsMonitor the boiler to ensure it returns to normal operation automatically

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Related fault codes

F.22View →F.73View →F.74View →

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