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.

Shared across the Basica Cond range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Related fault codes

E06View →

All 39 fault codes on the Basica Combi

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

E00E01E02E03E04E05E06E07E08E09E10E11E12E13E14E22E24E25E26E35E40E44E50E52E54E58Fault on gas supplyFaulty condensate drainageFaulty flame detectionFaulty gas valveFaulty ignitionJ01OFFP00P06P06 00P06 01P06 02

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