BoilerFaultCodesYour boiler's internal computer brain has experienced a critical error and can no longer control the heating system safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control box failure
What causes this fault?
This fault occurs when the boiler's internal computer experiences a catastrophic electronic failure, preventing it from processing safety information or managing the burner. The most common reason is the natural degradation of electrical components on the circuit board, which can sometimes be accelerated by power surges or moisture ingress. Because the brain of the boiler is no longer functioning correctly, it shuts down the system entirely to ensure your home remains safe.
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 42 — no call-out fees, no surprises.
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Remeha Quinta 30 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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