BoilerFaultCodesVokera AL55 Fault Code
The Vokera AL55 fault code means: your boiler's electronic control board has been set up with incorrect configuration settings or a missing physical connection, preventing it from operating.. It appears on 8 Vokera models in our database.
Technical description: Jumper tag fault
What causes the Vokera AL55 fault?
This fault occurs when the boiler's main control board is missing a small physical plug, known as a jumper, which tells the computer exactly which model it is installed in. It usually happens after a new circuit board has been fitted but not configured correctly, or if a component has vibrated loose over time. Without this specific hardware setting, the boiler shuts down for safety because it doesn't know its own operating limits.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Vokera models that show the AL55 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera AL55 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