BoilerFaultCodesYour boiler has switched itself off as a safety precaution because it detects that it is getting too hot or is unable to circulate water properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler safety shut down.
What causes this fault?
This fault occurs when the internal sensors detect that the water temperature has risen too quickly or exceeded safe limits, triggering an emergency shutdown to prevent damage. The most common reasons are a failed pump that isn't moving water around the system or a blockage within the heat exchanger caused by a buildup of limescale or sludge.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pump components to seize.
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 9 — no call-out fees, no surprises.
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