ActronAir Outdoor Coil Defrost Sensor D4 103AT 1.9m HT PVC is the high-temperature PVC variant of the outdoor defrost sensor for Classic Series residential split ducted systems, using a 103AT NTC thermistor in 1.9m high-temperature rated PVC cable for applications where the sensor routing path passes near the compressor or discharge line. The longer 1.9m cable compared to the standard 1.2m version accommodates larger outdoor unit cabinet configurations where the PCB is located further from the coil sensing point. Isolate power at mains before replacing any outdoor refrigeration sensors.