BoilerFaultCodesYour boiler has temporarily paused operation because it has reached its maximum temperature or detected a rapid temperature change.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Shut-off mode
What causes this fault?
This fault occurs when the boiler's internal water temperature rises too quickly or exceeds its safe operating limit, causing the system to pause to prevent overheating. The most common reasons are a pump failure that stops water from moving or a buildup of debris and sludge that creates a blockage within the pipework. It can also be triggered if the radiators are turned off or if there is air trapped in the system, preventing heat from being carried away.
This issue is more common during the first cold spell of autumn, when heating systems are switched back on after a long summer break and pump components may have seized.
DIY fix possible
Check that all radiator valves are open to ensure water can flowEnsure there is no air trapped in the system by bleeding your radiatorsCheck that the system pressure is between 1.0 and 1.5 bar on the pressure gauge
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