Low
202 on Worcester Bosch 24/28/35 CDi MkII

Your boiler is perfectly fine; it is simply waiting for a few minutes before turning the burner back on to prevent unnecessary cycling.

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 appliance is in optimised switching mode: the interval for restarting the burner has not yet expired ( service function 3-b2).

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual, page 65.
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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