BoilerFaultCodesYour boiler is unable to tell if its pump is running correctly, which means it has stopped working for your safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Error with pressure – no pressure change detection when starting the pump
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a slight jump in water pressure that should happen when the pump starts spinning. The most common reason is that the sensor itself is blocked with debris or has failed, but it can also be caused by a failing pump or a loss of air pressure in the expansion vessel. Essentially, the boiler shuts down because it cannot confirm that water is safely circulating through the system.
This fault is more frequent in autumn when the heating is turned back on after a long summer break, as pumps and sensors are more likely to seize or stick after periods of inactivity.
DIY fix possible
Check the pressure gauge and ensure it is between 1.0 and 1.5 barIf the pressure is too low, use the filling loop to top it upPress the 'Reset' button (flame symbol with a cross) once the pressure is correct
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