The Dwyer RLD2 refrigerant leak detector is a dependable negative corona refrigerant leak detector. The RLD2 has responsive elements with a wide sensitivity range and utilizes a five level alarm system to detect excessive refrigerant in areas where there could be a potential leak. The dual-color LED indicator lights provide visual indication of the refrigerant gas concentration, various audio pitches facilitate detection, and its portable design is convenient for the user. The RLD2 can be utilized in residential and commercial refrigeration systems, automotive, air conditioning, and quality control testing environments.