BoilerFaultCodesVokera E20 Fault Code
The Vokera E20 fault code means: your boiler has switched itself off completely as a protective measure because its internal safety sensors have detected a critical operating fault.. It appears on 1 Vokera model in our database.
Technical description: NTC3 short-circuited (NTC3 = sensor on the storage heater) Storage heater probe short-circuited
What causes the Vokera E20 fault?
This fault occurs when the boiler's internal components reach an unsafe temperature, triggering a complete shutdown to prevent damage. The most common reasons are a failure in the water circulation system, such as a faulty pump, or a defective sensor that is incorrectly reporting the heat levels to the control board.
This issue is more frequent during the first cold snap of winter when heating systems are suddenly pushed to run at high temperatures after being idle for months.
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 E20 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera E20 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