How to Convert a Refrigeration System from Mineral Oil to POE Oil Using a Refractometer

A practical guide to measuring residual refrigeration oil during a lubricant conversion

Converting an existing refrigeration system from mineral oil or another legacy lubricant to polyolester (POE) oil requires more than simply draining the compressor and adding new oil.

The objective is to remove as much of the original lubricant as practical and verify that the amount remaining is within the requirements established for the particular compressor, lubricant, refrigerant and application.

A refractometer provides a practical way to monitor that process.