Low
208 on Worcester Bosch Greenstar 4000

Your boiler is currently running its internal cooling process to safely lower the temperature of its components, which is a normal protective procedure.

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 pump will continue to run in order to cool the heat exchanger (visible when exiting chimney sweep mode).

From this model's manual
Verified against the Worcester Bosch Greenstar 4000 installation & service manual, page 71.
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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