4.10 Low

Keston 4.10 Fault Code

Also written as 410 — same fault.

The Keston 4.10 fault code means: your boiler is having trouble communicating with the weather sensor mounted on the outside of your property, so it is using a default setting to keep your home warm.. It appears on 1 Keston model in our database.

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.

Technical description: OUTSIDE SENSOR FAULT
Typical repair cost £100-200 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Keston models that show the 4.10 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Keston 4.10 fault code information on this page is sourced and cross-checked against the official Keston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026