Low Warning
54:0 on Viessmann Vitodens 300-W

Your boiler is confused because it is trying to communicate with a solar heating panel system that it cannot find or that isn't connected.

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 solar control unit

What causes this fault?

This fault occurs when the boiler's internal computer is incorrectly programmed to look for a solar thermal system that isn't actually there. It usually happens after a software update or a component replacement where the 'coding' hasn't been set correctly to match your home's specific setup. Essentially, the boiler is waiting for data from a solar control module that doesn't exist, leading to a communication error.

DIY fix possible

Locate the 'OK' and 'Menu' buttons (or the touchscreen menu).Navigate to the 'Service' or 'Settings' sub-menu.Restart the boiler using the main power switch to see if it clears the communication error.

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