Medium
13 on Unical Alkon C 28 HE

Your boiler is having trouble reading the temperature of your hot water supply due to a faulty sensor or loose wiring.

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

DOMESTIC HOT WATER SENSOR Domestic hot water sensor fault (1). Check the efficiency of the sensor (see table Res/Temp) (Par.4) or its connections.

From this model's manual
Verified against the Unical/Unical Alkon C 28 He 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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All 33 fault codes on the Alkon C 28 HE

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

14568091112141516171820212223242627303233384344455355758081

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