Medium
EE 3333 on Ariston Microsystem 15

Your boiler's internal fan is spinning even though you aren't trying to use your heating or hot water, which suggests a possible electronic sensor error.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Fan operation sensed with no demand for central heating or domestic hot water

Engineer required

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

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