BoilerFaultCodesYour boiler's electronic settings have been altered or are misconfigured, preventing it from operating correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Jumper 3 changed – check position of jumper 3.
What causes this fault?
This fault occurs when the internal electronic settings of the boiler have been accidentally altered or the configuration 'jumper' on the circuit board is in the wrong position. It usually happens during a repair or component replacement where the electronic settings haven't been correctly matched to your specific boiler model. Because the boiler's computer no longer knows exactly how it should be configured, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E.02 – .21 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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