Low
204 on Worcester Bosch Greenstar 12i System

Your boiler is temporarily pausing because it has already reached the target temperature you set for your radiators 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 waiting, primary flow temperature above set temperature point

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual, page 63.
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 or boiler dial settings to see if they are set lower than the current room temperature.Wait 10 to 15 minutes as the boiler will restart automatically once the water temperature drops.Ensure radiators are not turned off in every room, as the system needs a certain amount of flow to work correctly.

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