High
7.iii on Chaffoteaux Sterling FF

Your boiler has lost the air pressure needed to run smoothly, causing it to release excess water to prevent unsafe pressure levels within the system.

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

Safety valve discharges - Vessel lost air charge

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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