Low
2 04 on Ariston Clas One

Your boiler is having trouble communicating with the solar energy system because a heat sensor is disconnected or faulty, which may stop the solar panel integration from 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

Solar collector temperature probe open / short circuit

Engineer required

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

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Related fault codes

2 01View →2 02View →2 03View →

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