Emergency
9.iii on Chaffoteaux Sterling FF

Your boiler is overheating because it is burning more gas than it can safely process, causing the internal system to shut down to prevent damage.

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

Excessive temperature rise across boiler - Gas rate too high

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

9.iView →9.iiView →

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