Low
93 on Viessmann Vitodens 300-W

Your boiler has detected a technical fault with a sensor in your solar heating system, which means your solar panels may not be contributing to your hot water as they should.

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

Control mode: Solar: Sensor S3 shorted out

Engineer required

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

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Related fault codes

92View →9AView →9BView →

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