BoilerFaultCodesTechnical description
Code plug version: Coding plug version.
What causes this fault?
This fault occurs when the boiler's main control board cannot communicate correctly with the small electronic chip that tells it which specific model it is. The most common reason is that the coding plug has become loose, damaged, or is incompatible with the circuit board, leading the system to shut down for safety. In some cases, this happens following a power surge or if the internal memory on the main board has failed.
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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