High
F43 on Ferroli Domiproject

Your boiler has stopped working because it is getting too hot too quickly, usually because water isn't flowing through the pipes properly or there is trapped air.

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

Exchanger protection intervention – could be because no system water circulation or there’s air in the system

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

F05View →A03View →

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