High
F.33 on Vaillant ecoTEC Plus 826

Your boiler is struggling to detect that the fan is pushing air through properly, so it has safely shut down to prevent it from operating incorrectly.

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

Airpressureswitchfault

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.32View →F.61View →

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