Low Warning
7E:0 on Viessmann Vitodens 300-W

Your boiler has detected an incorrect setting regarding how its exhaust gases are vented, likely due to a setup error or a controller communication glitch.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Without flue gas cascade

What causes this fault?

This fault occurs when the boiler's internal computer has been told to look for other boilers to work alongside, but it cannot find any connected. It is usually triggered by an incorrect setting during a software update or if the wrong configuration code was entered when the main circuit board was replaced. Essentially, the boiler is waiting for communication from a 'team' of units that does not exist.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

7E:1View →F2View →

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