Low
i4 on Worcester Bosch Greenstar Heatslave II

This code is not actually an error; it is simply showing you the current maximum heating power level for your hot water production.

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 DHW output - The maximum possible DHW 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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