BoilerFaultCodesTechnical description
Main voltage error
What causes this fault?
This fault occurs when the boiler's internal computer detects that the incoming electricity supply is outside of the safe operating range. The most common reason is a power surge or a momentary spike in voltage that has affected the main circuit board's ability to monitor power safely. In some cases, it can also be triggered by loose internal wiring or a failing component that is drawing power incorrectly.
This fault is more common during autumn and winter storms, as lightning strikes or power grid fluctuations caused by high winds can trigger electrical surges.
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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