Medium
F11 on Ferroli iBoiler 24

Your boiler has lost its connection to the temperature sensor for your hot water, meaning the unit cannot accurately heat the water for your taps and showers.

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 (DHW) sensor error – sensor damaged, wiring shorted or disconnected

Engineer required

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

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Related fault codes

F10View →F14View →A03View →

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