BoilerFaultCodesYour boiler is currently undergoing a pre-set maintenance test or a specialized calibration check that lasts between 5 and 60 minutes.
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: Time adjustable from 5 to 60 minutes
What causes this fault?
This code appears when the boiler has been manually put into a specialized service mode, such as a chimney sweep test or a manual calibration check. It is triggered by a user or engineer adjusting the settings to run the burner at a specific output for a set duration. Once the programmed time for this test elapses, the boiler will automatically return to its normal heating operation.
DIY fix possible
Wait for the timer to count down and the code to disappear naturallyCheck that you haven't accidentally entered a test mode via the control panelIf the code persists for over an hour, try a simple reset of the boiler
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A boiler cover plan would cover faults like 9C:5 to 9C:60 — no call-out fees, no surprises.
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