8x High

Vokera 8x Fault Code

Also written as 8X — same fault.

The Vokera 8x fault code means: your boiler's main internal computer has developed a malfunction and can no longer control the heating system safely.. It appears on 3 Vokera models in our database.

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: PCB fault

What causes the Vokera 8x fault?

This fault occurs when the boiler's central control board suffers an internal hardware failure or a memory error, preventing it from processing safety data. The most common reasons are electrical surges, moisture ingress from a small internal leak, or simply the natural degradation of electrical components over time. Because the board can no longer communicate with the boiler's sensors, it shuts down the system entirely to prevent an unsafe operation.

Typical repair cost £280-450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Vokera models that show the 8x fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Vokera 8x fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026