Low
t3 on Worcester Bosch Greenstar CDi Compact

Your boiler is currently performing a routine check to ensure the water pump is working correctly before it starts heating your home.

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

Pump test. Checking the basic pump operation. The pump will run for a maximum of 45 seconds. If the pump is OK then the pump will be heard running.

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact 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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