Medium
50 on Atag iC28

Your boiler's hot water sensor has stopped working correctly, which means the system cannot accurately measure or provide hot 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

T3 (DHW) sensor error (e.g. open, short circuit, out of range)

From this model's manual
Verified against the Atag Ic28 installation & service manual, page 48.
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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