Medium
Er 12 on Biasi Advance 25C

Your boiler has sensed a problem with the internal sensor that monitors the temperature of the water returning from your radiators.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Faulty central heating temp. probe NTC (return)

From this model's manual
Verified against the Biasi Advance 25c installation & service manual, page 13.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Er 05View →Er 11View →Er 14View →

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