Low Warning
4.10 on Ideal Logic Max Heat

Your boiler has lost communication with the sensor that measures the temperature outdoors, which may cause your heating to run less efficiently.

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.

Technical description

Outside Sensor Fault

What causes this fault?

This fault occurs when the boiler's main control board loses the electronic signal from the sensor located on the outside of your home. The most common reasons are physical damage to the external sensor unit or the wiring connecting it to the boiler becoming loose, corroded, or damaged by the elements.

This fault is more common following periods of heavy rain or extreme frost, which can cause moisture to enter the sensor housing or cause the external wiring to perish.

Engineer required

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

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Related fault codes

4.11View →

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