BoilerFaultCodesTechnical description
System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's internal computer chips fail to communicate or 'handshake' with each other during the start-up sequence. It is usually caused by a physical hardware failure on the main circuit board or a loose connection in the internal wiring. Essentially, the boiler's brain has encountered a critical error that prevents it from safely managing the heating process.
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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