Emergency
Fig. 17 on Chaffoteaux Duo

Your boiler is releasing excess water because the internal pressure is too high or the safety valve has been triggered to prevent damage from overheating.

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

Discharge from temperature and pressure relief valve

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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