BoilerFaultCodesYour boiler is currently running a manual test mode at its lowest power setting, which is usually activated by an engineer during servicing.
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: Test program: Burner on at minimum power.
What causes this fault?
This code appears because a specific button sequence has been pressed to put the boiler into its manual 'low fire' test mode. It is almost always activated by an engineer during a service or safety check to measure gas pressure. If it appears unexpectedly, a button may have been bumped or the control panel could be sticking.
DIY fix possible
Press the 'Reset' button (or the 'Service' button) to exit the test mode.Turn the boiler off and back on at the fused spur switch to clear the temporary setting.If the code persists, check if any buttons are stuck or 'clicked in'.
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