Low
203 on Worcester Bosch Greenstar 8000+ GR8701iW 30 S

Your boiler is working correctly and is simply waiting for a signal from your thermostat or timer 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/Worcester Bosch Wb 47115 installation & service manual.
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 is turned up higher than the current room temperature.Ensure your heating programmer or app is set to an 'On' period.Check if your wireless thermostat has run out of batteries.

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Related fault codes

202View →204View →

All 103 fault codes on the Greenstar 8000+ GR8701iW 30 S

Seeing a different code? Every code this model can display, in one place.

2002012022042082142242272282292322332342352372382422442452462472482492502512522532542572582592622632652682692732812832843053063573583603623636048118151010101310171018101910221023102510371065106810701071107210751076208529082910291429152916292029232924292529262927292829312940294629482949295029512952295529562957296129622963296529662968296929702971297229802981

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