High
F5 on Heatline Vizo Plus

Your boiler has shut down because it can no longer safely measure the temperature of the exhaust gases leaving 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

Combustion product (flue) temperature probe damage

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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Related fault codes

F1View →F2View →F6View →

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