BoilerFaultCodesThe boiler's internal computer has encountered a communication error between its memory and control systems, which prevents it from running correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault U: Network CodeProblem is climate control system, lighting, airbags, etc..fault two; MFG – Manufacturer Specificfault four; Transmissionfault five; TP Sensor Learn Not Completefault three; Transmission Control Module Reprogrammable Memory
What causes this fault?
This fault occurs when the boiler's internal electronic brain suffers a data failure, meaning the different components can no longer talk to each other reliably. It is usually caused by a physical hardware failure within the circuit board or a corruption of the stored settings that dictate how the boiler should operate. Without this internal communication, the system shuts down as a safety precaution to avoid running blindly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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