Viessmann 2F:0 Fault Code
Also written as 2F0 — same fault.
The Viessmann 2F:0 fault code means: your boiler is currently stuck in an automated air-clearing or water-filling mode, meaning it cannot provide heat or hot water until the cycle is finished or reset.. It appears on 6 Viessmann models in our database.
Technical description: Ventilation program/filling program inactive
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Viessmann models that show the 2F:0 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Viessmann 2F:0 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