Low
H03 on Worcester Bosch Greenstar Ri

Your boiler has reached its programmed service interval and is simply reminding you that it is time for a routine annual safety check.

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

Planned maintenance required

From this model's manual
Verified against the Worcester Bosch Greenstar Ri installation & service manual, page 63.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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