BoilerFaultCodesTechnical description
System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's main control board and the front display panel lose the ability to talk to each other correctly. It is effectively a software 'crash' caused by a hardware failure, meaning the boiler can no longer verify that it is operating safely. The most common reason is an electrical component failure on the printed circuit board or a loose connection in the internal wiring.
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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