High
B LED 6 on Ferroli Arean

Your boiler has stopped working because it has detected a problem with either its water pressure, internal temperature sensors, or safety thermostats.

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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Related fault codes

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