BoilerFaultCodesVokera E37 Fault Code
The Vokera E37 fault code means: your boiler has detected an electrical wiring issue where the power supply wires are crossed, preventing it from safely lighting the flame.. It appears on 2 Vokera models in our database.
Technical description: Flame detection error – line and neutral reversed
What causes the Vokera E37 fault?
This fault occurs when the boiler detects that the electrical supply wires—the Live and Neutral—have been connected to the wrong terminals. It is most commonly caused by recent electrical work in the home or an incorrectly wired plug or fused spur that provides power to the unit. Because the boiler cannot safely monitor the flame with reversed polarity, it will prevent the system from firing 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 →Vokera models that show the E37 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera E37 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