High
LED 5 red (1) [DHW mode] on Ferroli Optima 201

Your boiler has detected an internal computer error and is currently unable to start, meaning you will likely have no hot water or heating.

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

Waiting time operating: replace P.C.B.

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

LED 3View →LED 4View →

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