High
B-6 on Ferroli Optima 201

Your boiler has stopped working because it has detected an issue with its water pressure or internal temperature monitoring systems.

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

C.H. sensor (34) short circuit or resistance lower than 500 ohm. C.H. limit thermostat (50) open circuit (pump will run). C.H. water pressure low (114 open circuit)

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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