Emergency
Er10 on Biasi ActivA 25C

Your boiler has detected that the temperature of the exhaust fumes passing through the flue is higher than it should be, causing the system to stop working as a safety precaution.

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

Flue temp. probe NTC - check Flue temp. probe NTC, Flue pipes

From this model's manual
Verified against the Biasi/Biasi Activa Service Manual July 2009 Pdf 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

Er01View →Er04View →

All 17 fault codes on the ActivA 25C

Seeing a different code? Every code this model can display, in one place.

E01E23Er01Er02Er03Er04Er05Er06Er07Er08Er09Er11Er14Er14+RESETEr99Li01

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