BoilerFaultCodesTechnical description
There is an internal fault in the Automatic Control Module.
What causes this fault?
This fault occurs when the boiler's central brain experiences a critical hardware failure or a memory error. The most common cause is the natural degradation of electronic components on the circuit board, which eventually prevents the unit from performing its safety checks. In some cases, electrical surges or moisture from a small internal leak can also damage these sensitive parts.
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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