BoilerFaultCodesWorcester Bosch 8/2/4 Fault Code
Also written as 824 — same fault.
The Worcester Bosch 8/2/4 fault code means: your boiler's control panel is looking for a remote thermostat that isn't connected, even though it is currently trying to run a frost protection program.. It appears on 1 Worcester Bosch model in our database.
Technical description: RC35-HK2 remote control. No remote control assigned, although frost protection type “FROST” has been set.
DIY fix possible
Locate the RC35 remote control unit or the boiler's main internal menu.Navigate to the heating settings and verify if a remote controller is assigned.If no remote is physically installed, change the frost protection setting to the internal sensor option or reset the thermostat configuration to match your actual setup.
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Worcester Bosch models that show the 8/2/4 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 8/2/4 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