High
A24 on Ferroli iBoiler 28

Your boiler's internal computer has become confused by its own settings and needs to be reconfigured by a professional to talk to the components correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Card parameter error – possibly wrong card parameter setting

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

A23View →F34View →F35View →

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