ActronAir Defrost Sensor 6m is an extended-length defrost sensor for large residential and light commercial ActronAir ducted systems where the distance between the outdoor coil sensing location and the outdoor PCB requires a 6-metre cable. The longer cable is used in applications where the standard 1.2m and 1.9m sensors cannot reach the PCB without additional splicing -- splicing temperature sensor cables introduces resistance that corrupts the thermistor reading, making the correct-length genuine sensor essential. Isolate power at mains before replacing any outdoor defrost sensors.