BoilerFaultCodesTechnical description
Fault history mode diagnostic code
What causes this fault?
This code appears when the boiler has been manually put into a high-performance test mode by a heating engineer during a service or inspection. It occurs because the boiler is bypasssing its normal temperature controls to run the fan at maximum speed for flue gas analysis. It is not a mechanical failure but rather a status indicator that the unit is being tested.
DIY fix possible
Locate the 'Mode' or 'Reset' knob/button on the front panel.Turn the selector knob away from the 'Service' or 'Spanner' icon back to 'Auto' or 'On'.Press the 'Reset' button once if the code persists after changing the mode.
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