Low
S.97 on Vaillant ecoTEC Plus 826

Your boiler is currently running a quick self-check on its internal sensors and has temporarily paused heating to ensure everything 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 test running, heating demands are blocked.

From this model's manual
Verified against the Vaillant Ecotec Plus 826 installation & service manual, page 48.
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 patiently for 5 to 10 minutes to see if the boiler completes the test automaticallyTurn the boiler off at the fused spur switch for 30 secondsTurn the boiler back on and allow it to restart its initialization sequence

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