How much does it cost to fix Viessmann error code 9C:5 to 9C:60?

Typical repair cost for the Viessmann 9C:5 to 9C:60 fault is £0-80 including labour.

9C:5 to 9C:60 Low

Viessmann 9C:5 to 9C:60 Fault Code

Q: What does the Viessmann 9C:5 to 9C:60 fault code mean?

Your boiler is currently undergoing a pre-set maintenance test or a specialized calibration check that lasts between 5 and 60 minutes.

Also written as 9C5TO9C60 — same fault.

The Viessmann 9C:5 to 9C:60 fault code means: your boiler is currently undergoing a pre-set maintenance test or a specialized calibration check that lasts between 5 and 60 minutes.. It appears on 5 Viessmann models in our database.

Technical description: Time adjustable from 5 to 60 minutes

What causes the Viessmann 9C:5 to 9C:60 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.

Typical repair cost £0-80 (including labour)

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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Viessmann models that show the 9C:5 to 9C:60 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Viessmann 9C:5 to 9C:60 fault code information on this page is sourced and cross-checked against the official Viessmann service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026