High
F3 on Ferroli Tempra

Your boiler has switched itself off because it has reached an unsafe temperature, usually due to the water inside not moving around properly.

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

The overheat safety thermostat tripped. Check the boiler water circulation and the thermostat.

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

F1View →F2View →

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