BoilerFaultCodesYour boiler is currently running a background self-test to check it can operate safely at its lowest power setting.
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 where the appliance is operated with minimum gas volume (ignition gas volume) after successful ignition
What causes this fault?
This code appears when the boiler automatically performs a internal calibration test to ensure it can sustain a stable flame at the lowest possible gas level. It is a normal part of the boiler's software routine and happens automatically after the burner ignites to verify efficiency and safety. You do not need to take any action as the boiler is simply checking its own homework before continuing to heat your home.
DIY fix possible
Wait for the test to complete automatically (usually takes 15 minutes)Press the 'Back' or 'Reset' button if the boiler appears stuck after 20 minutesTurn the power off and back on at the fused spur switch to restart the system
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