High
F4 on Ferroli Arean

Your boiler has switched off because the water pressure inside your heating system has dropped too low to operate safely.

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

Insufficient system pressure. Fill the system to 1-1.5 bar by use of the filling loop.

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

F37View →

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