Low
SH on Worcester Bosch CDi Classic

Your boiler is currently running a maintenance check at its maximum power, which is a normal process and not a fault with the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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