BoilerFaultCodesViessmann E16 Fault Code
The Viessmann E16 fault code means: your boiler has stopped heating because a safety sensor that monitors exhaust gases has detected an electrical fault.. It appears on 1 Viessmann model in our database.
Technical description: Burner does not start. Flue gas sensor fault (short circuit or lead break).
What causes the Viessmann E16 fault?
This fault occurs when the boiler's internal computer stops receiving a reliable signal from the sensor that monitors the temperature of the exhaust gases. It is usually caused by the sensor itself failing internally or the electrical wiring connecting it to the main control board becoming damaged or loose. Because this sensor is a vital safety component, the boiler stops immediately to prevent the system from 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 E16 fault code
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Source
Viessmann E16 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