Low
203 on Worcester Bosch Greenstar Ri

Your boiler is currently in a waiting state and is simply pausing because it has reached the temperature requested by your thermostat.

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 Ri 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 or smart controller settings to ensure it is calling for heatTurn the heating temperature dial on the boiler front panel up to see if the boiler activatesWait a few minutes to see if the system restarts naturally as the room cools down

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