Low
CH light flashing on Worcester Bosch Greenstar 25Si

Your boiler is currently taking a short, intentional break as part of its normal operating cycle to prevent overheating.

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

Three minute wait (CH light still on. Pump still On)

From this model's manual
Verified against the Worcester Boiler 28si 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.

Engineer required

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

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