BoilerFaultCodesYour boiler is temporarily running at its maximum power setting, which is usually a test mode activated during a service or inspection.
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: Forced full load.
What causes this fault?
This status occurs when the boiler has been manually put into a high-intensity test mode, often referred to as 'chimney sweep' mode. It happens because a technician is intentionally forcing the burner to its maximum output to measure gas pressure or calibrate emissions. It is not a failure of a component, but rather a specific operating state used for diagnostics.
This code is most common during the autumn or spring months when homeowners typically book their annual safety inspections and boiler services.
DIY fix possible
Press the 'Reset' button once to exit the test modeTurn the power off and back on at the fused spur switchWait for the boiler to complete its startup sequence and return to normal operation
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