BoilerFaultCodesYour boiler's internal computer has detected a safety control failure and has locked itself down as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety relay does not close
What causes this fault?
This fault occurs when the boiler's internal computer tries to engage a safety switch but detects that it has failed to close. The most common reason is a mechanical or electrical failure within the main circuit board, which prevents the system from confirming it is safe to ignite the burner. Because this involves a critical safety check, the boiler will prevent all operation to protect the household.
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 A06 — 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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