BoilerFaultCodesVokera E 04 Fault Code
Also written as E04 — same fault.
The Vokera E 04 fault code means: your boiler has stopped working because it has detected a major internal error that has forced it to shut down for safety reasons.. It appears on 1 Vokera model in our database.
Technical description: Appliance lockout and power failure
What causes the Vokera E 04 fault?
This fault occurs when the boiler's control system detects a complete interruption in electrical supply or a critical communication failure between internal components. It often happens because a fuse has blown on the main circuit board or because the board itself can no longer process power correctly. In some cases, loose wiring or a sudden power surge can trigger this emergency shutdown to protect the appliance from electrical damage.
DIY fix possible
Check if your main electrical consumer unit (fuse box) has any tripped switches.Ensure the boiler's power isolation switch is turned on.If power is present, try to reset the boiler using the control knob or reset button.
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Gas Safe Register →Vokera models that show the E 04 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera E 04 fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026