BoilerFaultCodesWhat the manual says
Manufacturer manualSupply voltage under 170V
From this model's manual
Verified against the Ferroli Bluehelix Tech installation & service manual, page 44.
What causes this fault?
This fault occurs when the electrical supply entering the boiler drops to a level that is too weak to power the internal components safely. The most common reason is an external issue with the local power grid, but it can also be triggered by a faulty control board inside the boiler that is misreading the incoming voltage.
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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