Emergency
Er10 on Biasi ActivA 18S

Your boiler has shut down because it has detected that the exhaust gases are becoming dangerously hot, which usually indicates a blockage or a heat exchange problem.

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

Lockout --- flue temperature probe NTC (Flue temperature > 120˚C)

From this model's manual
Verified against the Biasi Activa 18s 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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