Low
203 on Worcester Bosch Greenstar 8000 Life System

Your boiler is currently idle and functioning perfectly, simply waiting for a request from your thermostat or hot water tap to start heating.

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

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life System installation & service manual, page 67.
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 thermostat or programmer to ensure a heating or hot water schedule is activeIncrease the target temperature on your room thermostatEnsure your boiler is not set to 'Summer' or 'Hot Water Only' mode if you want heating

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