Low
203 on Worcester Bosch Greenstar 8000 Style GR8700iW 35 SB

Your boiler is perfectly healthy and simply waiting for a signal from your thermostat to turn on the heating or hot water.

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 Greenstar 8000 Life System 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

Turn up your room thermostat or smart controller settingsCheck that your hot water timer or programmer is set to 'On'Wait for a few minutes to see if the boiler fires up once a heat request is sent

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All 32 fault codes on the Greenstar 8000 Style GR8700iW 35 SB

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

200201202204208224227228305306306 V815815 B1017 W1022 B1065 B1068 W1075 W1076 W2920 V2927 B2946 V2948 B2950 B2963 B2964 B2965 B2966 B2967 B2970 B2971 B

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