BoilerFaultCodesYour boiler is temporarily pausing to check the system's water pressure before it starts up to provide heating or hot water.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Water pressure sensor check is running, demand (DHW or heating) is blocked
What causes this fault?
This fault occurs because the boiler's internal computer needs to verify there is enough water pressure in the system before it allows the burner to fire up. It is often caused by a slow-reacting pressure sensor or a slight delay in the system reaching the required pressure threshold after a long period of inactivity. While usually a brief check, if it persists, it suggests the sensor is struggling to send an accurate reading to the main control board.
This status is more frequent in autumn when the heating is turned back on for the first time, as system pressure can settle or drop slightly during the summer months.
DIY fix possible
Wait for 30 to 60 seconds to see if the code clears automaticallyCheck that the water pressure gauge is between 1.0 and 1.5 barTop up the water pressure using the filling loop if it is below 1.0 bar
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