BoilerFaultCodesMain E83 Fault Code
The Main E83 fault code means: your boiler's internal computer parts are having trouble talking to each other, which means the system has stopped working for safety.. It appears on 1 Main model in our database.
Technical description: Communication error
What causes the Main E83 fault?
This fault occurs when the boiler's internal control board loses touch with the display panel or the smart sensors inside the unit. It is usually caused by a loose connection in the wiring or a tiny electrical component failing due to age and heat. Because the brain of the boiler can no longer see what the rest of the components are doing, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Main models that show the E83 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Main E83 fault code information on this page is sourced and cross-checked against the official Main service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026