Leak detection in heating, ventilating and air conditioning systems using an environmentally safe material

A method of detecting leaks in a refrigeration system that uses in combination a refrigerant and a refrigeration system lubricant comprising the steps of:

• preparing a mixture that consists of said refrigeration system lubricant mixed with a predetermined amount of a dye selected from the general class of naphthalimide dye structures as a fluorescent dye;
• adding a predetermined amount of the mixture to said refrigerant for use in refrigeration system;
• operating the system for a predetermined period of time to allow the mixture to mix with said combination of refrigerant and the refrigeration system lubricant;
• examining the system for a leak site with a lamp that produces light having an emission wavelength from 300 to 480 nanometers, directed at said refrigeration system;
• determining the presence of a leak site by the presence of a colored fluorescence detectable by visual observation under the light from said lamp at said leak site;
• and said dye, refrigerant and refrigeration system lubricant mixture seeping thru and appearing at said location of leak site, the remaining at said site without undergoing chemical oxidation changes to provide capability for stable fluorescent indication of a leak.