High
08 on Saunier Duval Ecosy 24E

Your boiler is failing to start because it cannot confirm that the internal fan is effectively clearing exhaust gases, preventing it from safely igniting.

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

The Air pressure switch has not closed.

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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