BoilerFaultCodesWhat the manual says
Manufacturer manualNETWORK VOLTAGE TOO LOW: CHECK THE SAFETY ELECTRIC VALVE
From this model's manual
Verified against the Glow Worm Xtramax He installation & service manual.
What causes this fault?
This fault occurs when the electrical supply reaching the boiler's internal components drops below a safe working level. It is usually caused by an issue with the home's main power supply or a failing electronic part within the unit that can no longer process electricity correctly. Because the boiler cannot guarantee a safe ignition with such low power, it shuts down as a protective measure.
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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