BoilerFaultCodesTechnical description
Low supply voltage
What causes this fault?
This fault occurs when the electrical current entering the boiler drops below 175V, which is too low for the internal components to function. It is usually caused by a temporary fluctuation in the local power grid or an issue with the electrical wiring leading to the boiler. In some cases, a failing main control board inside the unit can also incorrectly detect a voltage drop that isn't actually there.
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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