Low
203 on Worcester Bosch Greenstar 2000

Your boiler is perfectly healthy and is simply waiting for you to turn on a tap or adjust your heating 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

Boiler in standby, no heat energy demand (Operating message, is not a fault)

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 79.
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 heating programmer is set to 'on'Ensure the hot water tap is fully open if you are testing for hot water

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