Medium Warning
79:0 on Viessmann Vitodens 333-F

Your boiler's internal control panel is having a communication error and is struggling to coordinate with other linked components in the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Control unit is not fault manager

What causes this fault?

This fault occurs when the main brain of the boiler loses its ability to lead the communication between different internal electronic parts. It is usually caused by a physical break in the wiring connections or a software glitch within the circuit board that prevents it from acting as the 'central manager' for the system.

DIY fix possible

Locate the main power switch for the boiler and turn it off.Wait for approximately 60 seconds.Turn the power back on and press the 'Reset' button on the front control panel.

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Related fault codes

79:1View →

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