Emergency
E01-944 on Worcester Bosch 24i RSF

Your boiler is struggling to clear exhaust gases due to an issue with the pipes that lead to the outside, which is preventing the system from running safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Vertical Flue Kit

From this model's manual
Verified against the Worcester Bosch 24i Rsf 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 is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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