High
Faulty condensate drainage on Biasi Basica Combi

Your boiler has stopped working because the pipe that carries away excess liquid is blocked or frozen, causing water to back up into the unit.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Obstruction or fault in the condensate drainage system

From this model's manual
Verified against the Biasi Basica Combi 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 high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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