Your boiler’s internal computer has lost its configuration settings and no longer knows how to run safely.

Jumper tag fault

What causes this fault?

This fault occurs when the boiler's main control board loses its identity because the small plastic 'jumper' connectors that tell it which model it is have failed or become loose. Essentially, the boiler has developed amnesia and has shut down as a safety precaution because it no longer knows its own operating parameters. The most common reason is a malfunctioning circuit board or physical degradation of the jumper tags due to age.