Low
203 on Worcester Bosch Heatslave

Your boiler is currently in standby mode and waiting for a signal from your thermostat or timer to begin 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

The boiler is on standby

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 temperature.Ensure your heating programmer or timer is set to 'ON'.Check if your hot water tank is already up to temperature.

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Related fault codes

201View →202View →204View →

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