Low
203 0 on Worcester Bosch Heatslave

Your boiler is working correctly and is simply waiting for you to turn up your thermostat or programmer to request heat.

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 Heatslave 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 temperatureEnsure your heating programmer or timer is set to an 'ON' periodCheck that your thermostatic radiator valves (TRVs) are open

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