Low
203 on Worcester Bosch Greenstar 4000

Your boiler is working perfectly fine 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.

Technical description

Boiler in standby, no heat energy demand - Appliance in standby, awaiting a demand request.

DIY fix possible

Check your thermostat or programmer is set to 'on' or 'timed'Increase the target temperature on your room thermostatTurn on a hot water tap to see if the boiler fires up

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