BoilerFaultCodesWhat the manual says
Manufacturer manualPower supply <170V
From this model's manual
Verified against the Glow Worm Cxi Csi System installation & service manual, page 37.
What causes this fault?
This fault occurs when the electrical supply entering your boiler drops to a level that is too low for the internal components to function. It is usually caused by a wider problem with the local power grid or a fault within your home's electrical wiring that prevents the boiler from receiving a steady 230V flow. In some cases, it can also mean the boiler's internal control board is failing to correctly process the incoming power.
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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