Emergency
C13 on Main Eco Compact Combi

Your boiler is struggling to bring enough fresh air in or push exhaust gases out, which has triggered a safety shut-down to prevent harmful fumes from entering your home.

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

Boiler type C13

From this model's manual
Verified against the Main Eco Compact Combi installation & service manual, page 12.
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

C12View →C14View →

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