Worcester Bosch No mains LED Fault Code
Also written as NOMAINSLED — same fault.
The Worcester Bosch No mains LED fault code means: your boiler has completely lost power and is unable to turn on, likely due to a blown fuse or a failure in the electrical control board.. It appears on 1 Worcester Bosch model in our database.
Technical description: Failure of mains supply, blown fuse (F1 2ATHRC or F2 1.25AT), or faulty PCB.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Worcester Bosch models that show the No mains LED fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch No mains LED 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 27 April 2026