BoilerFaultCodesYour boiler's internal control board has become too hot and has shut down the system to prevent any electrical damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Electronic temperature too high
What causes this fault?
This fault occurs when the boiler’s central brain, the PCB, reaches an unsafe operating temperature. It is usually caused by heat radiating from a failing internal component or poor ventilation around the control box itself. To prevent the delicate electronics from melting or catching fire, the system instantly shuts down as a safety precaution.
This fault is more common during the peak of winter when the boiler is running at maximum capacity for long periods, leading to higher internal temperatures within the casing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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