BoilerFaultCodesTechnical description
System fault
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to talk to other internal electronic components. It is physically caused by a break in the electrical signal, often due to a loose wiring connection or a component failure on the circuit board itself. Because the 'brain' of the boiler cannot verify that all systems are safe, it shuts down immediately to prevent damage.
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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