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.

Technical description

Boiler in standby – no heat energy demand

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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Related fault codes

202View →204View →

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