Low
12 on Alpha E-Tec Plus 10 / 18

Your boiler has detected an issue with a temperature sensor that monitors incoming water, which can affect how efficiently it provides hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Optional DHW inlet sensor resistance out of range

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 47.
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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