BoilerFaultCodesViessmann FE Fault Code
The Viessmann FE fault code means: your boiler's internal computer has encountered a critical error or is having trouble communicating with its electronic security card, causing the system to shut down for safety.. It appears on 9 Viessmann models in our database.
Technical description: Burner blocked. Strong interference (EMC) field nearby; alternatively boiler coding card or main PCB faulty. Remove EMC interference. If the equipment will not restart, check the boiler coding card and replace, or replace the control unit.
What causes the Viessmann FE fault?
This fault occurs when the boiler's main control board loses its connection with the small electronic chip that tells it how to operate safely. It is usually caused by electrical interference, a loose chip connection, or a physical failure within the central circuit board itself. Because the boiler no longer knows its own safety parameters, it shuts down immediately to prevent damage.
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 FE fault code
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Source
Viessmann FE 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