Medium
2 yellow on Ferroli Combi 77 FF Popular

Your boiler thinks you are running a hot tap even when they are all turned off, which may cause the heating to stay off or the internal water to overheat.

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

Domestic hot water flow switch (38) on

Engineer required

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

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