BoilerFaultCodesYour boiler has temporarily paused itself because it detected that the water temperature is rising too quickly, suggesting there isn't enough water circulating through the system.
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: Appliance is within the waiting period of the operation block function due to water shortage (temperature gradient)
What causes this fault?
This fault occurs when the boiler's internal sensors detect the heat exchanger getting hot much faster than expected, indicating that heat isn't being carried away by the water. The most common reason is low water pressure or a blockage that is preventing the water from flowing freely through the radiators. It can also happen if your pump has seized or if all your radiator valves are turned off at once.
This fault is frequently seen in autumn when heating systems are first turned back on after summer, as pump components can seize during long periods of inactivity.
DIY fix possible
Check the pressure gauge on the boiler front or digital display and ensure it is between 1.0 and 1.5 bar.If pressure is low, use the filling loop underneath the boiler to top it up.Ensure all radiator valves and the boiler isolation valves are fully open.Bleed your radiators to remove any trapped air pockets.
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