Medium
Pr 29 on Biasi Advance 25C

Your boiler has detected an issue with the sensor that monitors the temperature of the cold water coming into the unit, which can affect its ability to heat your water correctly.

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

Presence of domestic cold water temp. probe or set of inlet cold water with solar control

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

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