Low
203 0 on Worcester Bosch 35 RSF

Your boiler is working fine but is currently sitting idle because your thermostat or hot water tap hasn't asked it to turn on.

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 temperature.Ensure your heating programmer or timer is set to an 'ON' period.Check if any wireless thermostat batteries need replacing.

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Related fault codes

200View →201View →

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