Emergency
TTB Trip on Potterton Osprey CF 125

Your boiler has detected that hot exhaust fumes are not escaping properly through the flue and has switched itself off to prevent poisonous gases from entering your home.

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

This device is a safety feature... If the unit continues to trip then the flue should be checked for spillage.

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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