High
LED 6 (A) on Ferroli Hawk II

Your boiler has stopped working because it is unable to accurately detect the water pressure or temperature, preventing it from safely heating your home or water.

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.

What the manual says

Manufacturer manual

Short circuit on D.H.W. sensor (42) or resistance lower than 500 Ohm; C.H. limit thermostat (50) open circuit (pump run); C.H. water pressure low (114 open circuit)

From this model's manual
Verified against the Ferroli Boiler Hawk Ii installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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