Low Warning
54:1 on Viessmann Vitodens 300-W

Your boiler's solar control system is having trouble communicating with its temperature sensors or the pump, meaning your solar water heating may not be working correctly.

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

With Vitosolic 100

What causes this fault?

This fault occurs when the main boiler loses its connection with the Vitosolic solar control module, essentially causing a breakdown in communication between the two systems. The most common reason is a loose or damaged data cable, though a malfunction within the solar controller itself can also trigger the alert.

This fault is often more noticeable during the summer months when the household relies more heavily on solar energy rather than gas to heat their water.

Engineer required

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

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Related fault codes

54:2View →

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