BoilerFaultCodesYour boiler is unable to sense water moving or pressure building when it tries to start up, which has caused it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No pressure change detected when starting the pump
What causes this fault?
This fault occurs when the boiler's internal computer fails to detect a rise in water pressure after it tells the pump to start spinning. The most common reason is that the pressure sensor has become blocked with sludge or has failed, but it can also happen if the pump itself has seized or if there is not enough water in the system to move.
This fault is more frequent in autumn when the heating is turned on for the first time after summer, as the pump can seize or 'stick' after long periods of inactivity.
DIY fix possible
Check the pressure gauge and ensure it is between 1.0 and 1.5 barIf pressure is too low, use the filling loop to top it upReset the boiler to see if the fault clears
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