BoilerFaultCodesWhat the manual says
Manufacturer manualLOW MAINS VOLTAGE - CONTACT ELECTRICITY PROVIDER
What causes this fault?
This fault occurs when the electrical supply entering your home drops below the minimum voltage required for the boiler's sensitive electronics to function. While it is often caused by a temporary dip or brownout in the local power grid, it can also be triggered if the boiler's internal control board develops a fault and can no longer process the incoming power correctly.
This fault can be more common during periods of extreme cold or heatwaves when the national electricity grid is under high demand, leading to localized voltage drops.
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.
Avoid the next call-out bill
A cover plan would handle faults like F7: no call-out fees, no surprise bills.
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