BoilerFaultCodesTechnical description
Control device version: Software version of the control unit.
What causes this fault?
This fault occurs when the boiler's main control board loses communication with its internal memory or cannot verify its own software. It is essentially a digital handshake failure between the central processing unit and the specific data chip that tells the boiler how to operate safely. The most common reason is an electronic component failure within the printed circuit board or a corruption of the software on the code plug.
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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