High
F47 on Ferroli Optimax

Your boiler has lost communication with a built-in water pressure sensor, meaning it cannot confirm there is enough water 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

N/A for UK market (Wiring interrupted / Sensor damaged)

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 →F40View →

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