High
F83 on Heatline Monza

Your boiler has detected that there is not enough water circulating inside the system to carry the heat away safely, so it has turned itself off to prevent damage.

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

No water in the installation : the temperature does not increase when the burner is lit

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

F22View →

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