Low Warning
Outside Sensor Fault on Ideal Logic Max Heat

Your boiler has lost connection with the sensor that measures the temperature outside, meaning it may not heat your home as efficiently as usual.

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

Wiring or resistance issues with the external outside temperature sensor.

What causes this fault?

This fault occurs when the boiler can no longer communicate with the small sensor box located on your external wall. The most common reasons are moisture entering the sensor casing causing corrosion, or a break in the thin communication wire leading back to the boiler.

This fault is more frequent during autumn and winter when increased rainfall and freezing temperatures can damage exposed external wiring or sensor seals.

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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