Medium
S.33 on Vaillant ecoTEC plus System

Your boiler is temporarily waiting for its internal air pressure system to reset before it can safely start the ignition process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Forced fan operation until the pressure monitor is switched

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.32View →F.33View →

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