A self-orienting sensing system for a heating, ventilation, and air conditioning (HVAC) system includes a housing having a main body. The housing defines a sensing aperture in a first portion of the main body and a mounting channel in a second portion of the main body. The self-orienting sensing system includes a sensing element retained within the housing. The sensing element is configured to detect leaked refrigerant that enters the housing via the sensing aperture. The self-orienting sensing system also includes a mounting retainer configured to extend through the mounting channel and couple the housing to an interior surface of an air handling enclosure of the HVAC system. The mounting retainer enables the mounting channel to rotate about the mounting retainer to automatically align the sensing aperture in a target sensing orientation based on a weight of the housing under the force of gravity.