SH Low

Worcester Bosch SH Fault Code

The Worcester Bosch SH fault code means: your boiler is currently running a maintenance check at its maximum power, which is a normal process and not a fault with the system.. It appears on 1 Worcester Bosch model in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: The display (C) will alternate between SH and the central heating flow temperature. Performance test mode (maximum output) is active.

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 SH fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch SH 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