High
Operation lights flashing on Biasi Riva Compact HE M96a

Your boiler is starting up briefly but then switching itself off because it is struggling to safely expel waste gases or drain excess condensation.

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

The boiler lights for a short while in c.h. mode (Condensate drain pipe and trap / Air pressure sensor / Flue pipes defect).

From this model's manual
Verified against the Riva Compact He M96a System Service 2008 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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