Viessmann 32:0 Fault Code
Also written as 320 — same fault.
The Viessmann 32:0 fault code means: your boiler has been forced to shut down its water circulation pumps by an external safety device or a control signal from your heating system's management unit.. It appears on 5 Viessmann models in our database.
Technical description: Influence of 'External lockout' signal on circulation pumps: All pumps are controlled
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 32:0 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Viessmann 32:0 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