High Lockout
E 13 on Vokera Hydra

Your boiler's main control unit has identified a critical internal software or hardware error and must shut down to prevent further damage.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Internal fault (PCB)

What causes this fault?

This fault occurs when the boiler's internal computer experiences a critical communication breakdown or a physical component failure on the circuitry. It is often caused by an electrical surge, moisture getting onto the board, or simply the natural degradation of the solder joints and microchips over time.

This fault is slightly more common during the winter months, as the increased workload on the boiler can push an aging or stressed circuit board to the point of total failure.

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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