BoilerFaultCodesYour boiler is currently running in a manual test mode used by engineers and is not experiencing an actual fault.
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: Burner on at minimum power (Test Program)
What causes this fault?
This code appears when the boiler has been manually put into a low-power testing mode, usually by an engineer during a service or repair. It occurs because the control buttons were pressed in a specific sequence to lock the burner at its minimum setting for combustion analysis. This is a status indicator rather than a component failure, so your boiler is simply waiting for the test to be finished.
DIY fix possible
Press the + and - buttons simultaneously to exit the test modeIf the code persists, press the Reset buttonSwitch the boiler off and back on at the fused spur switch
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