Standley & Gilcrest
Method for changing lubricant types in refrigeration or air conditioning machinery using lubricant overcharge
 The present invention includes a method for changing lubricant types in closed cooling systems such as refrigeration, air-conditioning machinery, and the like. The present invention is also applicable to heat pumps. The method of the present invention may be used on such systems that comprise one or more compressors, one or more evaporators, and one or more condensers. The method of the present invention allows the original compressor lubricant to be drained and replaced with a new lubricant; typically a lubricant of a different type than the original lubricant. Through use of the method of the present invention, all accessible points in the system (i.e., the compressor, the high side oil separator, if so equipped, and the accumulator, if so equipped, etc.) may be drained of the original lubricant and recharged with a new lubricant. After this is done, the original lubricant may still remain in the evaporator, condenser, and/or associated fluid lines. 
Integral Sciences Incorporated
F F
F25B F25B
additional inventional
Michael E. Robert John J.
Shows Yost Byrne