Medium
A5 on Worcester Bosch Ri 25 HE

Your boiler is struggling to accurately detect the temperature of the water used for your heating and hot water, which may cause it to stop working correctly as a precaution.

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

Heat store NTC sensor 2 defective

Shared across the 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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All 9 fault codes on the Ri 25 HE

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

00 - FFA1A8C4d1E0F0FC

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