Your boiler has detected an internal electrical safety failure and has shut down to prevent an unsafe operating condition.
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 open
What causes this fault?
This fault occurs when a critical internal electrical component, known as a safety relay, becomes stuck in the closed position on the control board. The boiler detects that it can no longer physically cut the power to vital components if it needed to, so it shuts down as a protective measure. The most common reason for this is electrical wear and tear or a hardware failure within the boiler's main control box.
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 A07 — 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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