Low
203 on Worcester Bosch Greenstar CDi Compact

Your boiler is currently in a temporary holding state while it waits for a signal from your thermostat or hot water tap to start 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.

Technical description

System stand by

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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