Low Warning
FE96 on Alpha Pro Tec Plus

Your boiler is struggling to detect the outside temperature, so it is temporarily running on a backup setting to keep your home warm.

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

External sensor fault.

What causes this fault?

This fault occurs when the boiler loses its connection to the sensor mounted on the outside of your home. It usually happens because the sensor itself has failed due to water ingress or because the external wiring has become damaged or corroded over time.

This fault is often noticed during the transition into autumn or winter when the boiler relies more heavily on the sensor to calculate the heat needed for the home.

Engineer required

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

Find a Gas Safe engineer
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