BoilerFaultCodesTechnical description
Fault with mains supply, PCB fuse or low water pressure switch.
What causes this fault?
This fault occurs when the boiler's internal computer stops receiving a steady flow of electricity or detects that the system doesn't have enough water to function. The most common reason is a simple drop in water pressure, but it can also be triggered by a blown internal fuse or a failing main circuit board. Because the boiler cannot guarantee it will run safely under these conditions, it shuts down entirely 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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