Low
203 on Worcester Bosch Greenstar i

Your boiler is currently in a waiting state where it has temporarily paused operation because it has reached the temperature set on your thermostat or controls.

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

From this model's manual
Verified against the Worcester Bosch Greenstar I installation & service manual, page 37.
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 your room thermostat to ensure the target temperature is set higher than the current room temperatureEnsure your heating timer or programmer is currently set to an 'On' periodIf your hot water is also not working, verify that the hot water cylinder thermostat or combi timer settings are active

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