Worcester Bosch 285 Fault Code
The Worcester Bosch 285 fault code means: your boiler has detected that the water returning to it is much hotter than expected, suggesting heat isn't circulating properly through your radiators.. It appears on 4 Worcester Bosch models in our database.
Technical description: Return temperature is too hot
What causes the Worcester Bosch 285 fault?
Overtemperature at return
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 285 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 285 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