BoilerFaultCodesYour boiler has detected an internal error and is waiting for you to look at the display to reveal the specific fault code causing the problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Displays during a fault condition with diagnostic and status code
What causes this fault?
The 'Alert' notification appears when the boiler’s central brain detects that a specific component is no longer operating within its safe or expected limits. This usually happens because an internal part, like a sensor or the fan, has either failed completely or is sending inconsistent data to the control board. It acts as a protective 'blanket' message that stops the boiler to prevent further damage until the underlying technical issue is identified.
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 Alert — 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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