BoilerFaultCodesWorcester Bosch 258 Fault Code
The Worcester Bosch 258 fault code means: your boiler's internal computer has encountered a software or hardware communication error and has stopped working to protect itself.. It appears on 8 Worcester Bosch models in our database.
Technical description: System fault boiler electronics / basic controller
What causes the Worcester Bosch 258 fault?
This fault occurs when the boiler's internal computer chips fail to talk to each other correctly, leading to a total communication breakdown between the main brain and the control panel. The most common reason is a physical hardware failure on the main circuit board or a corruption in the software that manages the boiler's safety checks.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Worcester Bosch models that show the 258 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 258 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