Low
9A on Viessmann Vitodens 300-W

Your boiler has lost its connection to the solar panel temperature sensor, meaning it cannot monitor how much heat is coming from your solar system.

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: Collector temperature sensor lead break

Engineer required

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

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Related fault codes

9BView →

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