Low
i23 on Worcester Bosch Greenstar Heatslave II

Your boiler is simply displaying its internal software version information rather than reporting a functional problem.

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.

What the manual says

Manufacturer manual

HCM version number - For example “4”

From this model's manual
Verified against the Worcester Bosch Greenstar Heatslave Ii installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Press the 'Reset' button on the boiler control panel onceWait for the display to return to the standard temperature readingIf it persists, turn the boiler off at the fused spur for 30 seconds and switch it back on

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