Low
201 on Worcester Bosch Greenstar 30i

Your boiler is simply indicating that it is currently busy heating your water and there is no actual fault to worry about.

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

The boiler is in domestic hot water (DHW) mode

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

Turn off any running hot water tapsCheck if the code disappears once the hot water is no longer in useMonitor the boiler for any alternative flashing lights if the water stays cold

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