High
S.97 on Vaillant Home System

Your boiler has paused itself to run a safety check on its internal water pressure sensor, meaning your heating and hot water are temporarily unavailable.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

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

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.22View →F.73View →F.74View →

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