Medium
E28 on Biasi Basica Combi

Your boiler's hot water sensor has malfunctioned or developed a wiring fault, meaning the system can no longer monitor the temperature of your stored water.

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

Tank NTC probe failure.

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

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