452 High

Viessmann 452 Fault Code

The Viessmann 452 fault code means: your boiler's internal computer has encountered a software timing error, causing it to stop running for safety.. It appears on 1 Viessmann model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Error in scheduled program run monitoring
Typical repair cost £100-250 (including labour)

DIY fix possible

Locate the power switch for the boiler and turn it off for 30 seconds.Turn the power back on and wait for the system to reboot.Press the Reset button on the control panel if the fault code persists.

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Viessmann models that show the 452 fault code

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

Source

Viessmann 452 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 7 July 2026