Emergency
E01-600 on Worcester Bosch 24i RSF

Your boiler has detected an issue with the protective insulation lining inside the combustion chamber, which is a safety-critical part that keeps the heat contained.

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

Insulation Pack

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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Related fault codes

E01-602View →E01-603View →

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