BoilerFaultCodesTechnical description
Jumper 1 changed – check position of jumper 1.
What causes this fault?
This fault occurs when the boiler's control board detects that a physical configuration pin, known as a jumper, has been moved or is missing. It acts as a safety mismatch because the internal computer no longer recognizes which specific model or power setting it should be operating at. The most common reason is a component failure on the main circuit board or an accidental change made during a recent repair or board replacement.
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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