Low
203 on Worcester Bosch Greenstar Heatslave II

Your boiler is currently in standby mode and is working exactly as it should because there is no current request for heat or hot water.

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

System stand-by: The boiler has no CH or DHW demands.

From this model's manual
Verified against the Worcester Bosch Greenstar Heatslave Ii installation & service manual, page 29.
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

Check that your room thermostat or smart controller is set to a temperature higher than the current room temperatureEnsure your heating timer or schedule is currently set to 'ON'Check that the hot water pre-heat function or your hot water schedule is active if you need an immediate hot water supply

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