BoilerFaultCodesTechnical description
User interface connection fault. Check wiring between mainboard and user interface
What causes this fault?
This fault occurs when the data link between the boiler's internal computer and the front display panel is broken, preventing the two parts from 'talking' to each other. It is usually caused by a loose plug, a damaged wire, or a failing electronic chip on one of the circuit boards. Because the boiler cannot confirm its settings or safety parameters, it stops running as a precaution.
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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