BoilerFaultCodesTechnical description
Ion base value lower than the upper factory limit, try resetting the boiler
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a strong enough electrical signal from the flame during operation. It is often caused by a dirty or worn-out sensing electrode, though it can also happen if the burner isn't receiving the correct mix of gas and air. To protect your safety, the boiler stops when it cannot verify that the gas is burning correctly.
DIY fix possible
Locate the reset button (usually a circular arrow or 'Reset' text) on the control panel.Press and hold the reset button for five seconds.Wait for the boiler to restart and monitor if the code clears.
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