BoilerFaultCodesYour boiler's internal computer has developed a fault and is unable to send the correct signals to start the heating process.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Defective control panel.
What causes this fault?
This fault occurs when the boiler's internal computer brain, known as the PCB, suffers a hardware failure or a communication breakdown between its main circuits. The most common reason is electronic component wear or a power surge that has damaged the delicate circuitry required to manage the boiler's operations.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 7L — no call-out fees, no surprises.
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