Medium
F11 on Ferroli iBoiler 28

Your boiler is struggling to accurately measure the temperature of your hot water, which usually means your taps will only run cold.

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 →A06View →

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