High
EE 3344 on Ariston E-Combi One

Your boiler is failing to start because it cannot confirm that air is moving through the system correctly, which is a necessary safety check before ignition.

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

Fan operation but air pressure switch does not close

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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