Worcester Bosch E01-940 Fault Code
Also written as E01940 — same fault.
The Worcester Bosch E01-940 fault code means: your boiler has detected that it is currently set up for a different type of gas fuel than it is receiving, which prevents it from operating safely.. It appears on 1 Worcester Bosch model in our database.
Technical description: Gas Conversion Kit NG to LPG
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Worcester Bosch models that show the E01-940 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch E01-940 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026