Genuine Daikin 153475J Thermistor Housing is the housing that holds and protects a thermistor in the unit, keeping it located correctly for an accurate reading. When it is broken or missing, the sensor can sit wrong, read inaccurately, and the unit can run unpredictably. A genuine housing locates the sensor the way your Daikin expects — where a non-genuine part can let it sit out of position.