Low
i3 on Worcester Bosch Greenstar Heatslave II

Your boiler is simply displaying its current heating power limit and is not actually experiencing a fault or error.

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

Maximum CH output - The maximum possible CH output is displayed in kW.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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