High
F.32 on Vaillant aquaPLUS

Your boiler has stopped working because the fan is spinning at the wrong speed, causing the system to lock as a safety precaution.

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

Main heat exchanger anti freeze protection mode due to fan speed deviation too great | Check fan control cables/connections; Defective fan control cable;

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.20View →F.33View →

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