Emergency
F5 on Heatline Capriz Plus

Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust fumes, so it has shut down to keep your home safe.

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

Combustion product (flue) temperature probe damage

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

F4View →

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