Emergency
S.33 on Vaillant Turbomax Plus VUW 242E

Your boiler has paused because it is struggling to breathe clearly, meaning it cannot pull in fresh air or push out exhaust fumes correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Check air/flue system

Engineer required

This is a emergency 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.33View →F.32View →

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