BoilerFaultCodesViessmann E13 Fault Code
The Viessmann E13 fault code means: your boiler has stopped heating because it is unable to accurately measure the water temperature flowing through the pipes.. It appears on 1 Viessmann model in our database.
Technical description: Burner does not start. Flow sensor fault (short circuit or lead break).
What causes the Viessmann E13 fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the heat of the water leaving the unit. It is usually caused by the sensor's internal electronics failing or the connecting wires becoming damaged or loose. Without this data, the boiler shuts down as a safety precaution to prevent the system from dangerously overheating.
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 E13 fault code
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Source
Viessmann E13 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