BoilerFaultCodesThe main computer board inside your boiler has detected a software error or an internal malfunction and is unable to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal control box error
What causes this fault?
This fault occurs when the boiler's internal computer experiences a critical communication failure or a component failure on the circuit board itself. It is essentially a 'system crash' where the control box can no longer safely monitor the boiler's operations, leading it to shut down for safety. The most common reason is the natural degradation of electrical components over time or a sudden power surge that has damaged the delicate circuitry.
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 E03 — no call-out fees, no surprises.
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Remeha Selecta is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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