Guangzhou Zhongleng teaches you how to determine whether refrigeration oil has deteriorated.

How can you tell if refrigeration oil has deteriorated? Many people outside the industry aren’t entirely sure. In this issue, Guangzhou Zhongleng’s editor has compiled relevant information to help you determine whether your refrigeration oil has gone bad—let’s take a look.

The primary causes of degradation are varied; they may include the ingress of moisture, oxidation, or the mixing of several different grades of refrigeration oil.

Deterioration of refrigeration oil can reduce its viscosity and even compromise the formation of an oil film, leading to bearing damage. Moreover, if two types of refrigeration oils contain antioxidant additives with differing chemical properties, their mixing may trigger chemical reactions that produce precipitates, thereby impairing compressor lubrication. Therefore, caution should be exercised when using such oils.

How can you tell if refrigeration oil has deteriorated?
(1) Drop Paper Method
Take a clean white sheet of paper, extract a small amount of refrigeration oil from the compressor housing, and place it on the paper. After a short while, examine the color of the oil spot: if the spot is very light and evenly distributed, the refrigeration oil is of good quality and can continue to be used; if you observe dark spots or rings on the paper, it indicates that the refrigeration oil has deteriorated or contains excessive impurities, and replacement should be considered.
(2) Comparative Method
Take several samples of unused refrigeration lubricant, pour them into clean glass test tubes or graduated cylinders, and allow them to stand for a period of time; these will serve as the standard reference samples. Then, extract a small amount of the refrigeration lubricant to be evaluated from the compressor and transfer it to another identical container; visually compare the two. If the color and transparency of the sample taken from the compressor are similar to those of the standard refrigeration lubricant, it indicates that the lubricant has not deteriorated. However, if the sample from the compressor exhibits noticeable differences—appearing as an opaque orange‑red or reddish‑brown hue—it signifies that the refrigeration lubricant has degraded and should no longer be used; the lubricant must be replaced.

Guangzhou Zhongleng Trading Co., Ltd. specializes in the distribution of genuine refrigeration materials and serves as an authorized distributor and partner to numerous reputable brands. Our core product lines include refrigeration oils, refrigerants, and refrigeration accessories. With all necessary certifications, we are committed to providing high‑quality refrigeration products to our customers.