BoilerFaultCodesYour boiler has detected an internal communication error or a software glitch that is preventing the system from starting up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Current fault: Fault code (table 10.1.2)
What causes this fault?
This fault occurs when the boiler's main control board loses touch with the internal components it needs to manage, often due to a breakdown in electronic communication. The most common reason is a malfunction within the Printed Circuit Board itself or a loose connection in the wiring harness that carries signals throughout the unit. Because the 'brain' of the boiler can no longer verify that it is safe to operate, it stops the system from firing up.
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 1-A2 — 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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