Oil Additives - Emerson Copeland Scroll YH04K1E Application Manuallines

Figure 18: Absorption of moisture in ester oil in comparison to mineral oil in ppm by weight at 25 °C and 50 % relative
humidity (h=hours)
If the moisture content of the oil in a refrigeration system reaches unacceptably high levels, corrosion
and copper plating may occur. The system should be evacuated down to 0.3 mbar or lower. If there
is uncertainty as to the moisture content in the system, an oil sample should be taken and tested for
moisture. Sight glass/moisture indicators currently available can be used with the A2L refrigerant and
lubricants; however, the moisture indicator will just show the moisture contents of the refrigerant. The
actual moisture level of POE would be higher than the sight glass indicates. This is due to the high
hygroscopicity of the POE oil. To determine the actual moisture content of the lubricant, samples
have to be taken from the system and analysed.
6.8

Oil additives

Although Emerson cannot comment on any specific product, from our own testing and past
experience, we do not recommend the use of any additives to reduce compressor bearing losses or
for any other purpose. Furthermore, the long-term chemical stability of any additive in the presence
of refrigerant, low and high temperatures, and materials commonly found in refrigeration systems is
complex and difficult to evaluate without rigorously controlled chemical laboratory testing. The use
of additives without adequate testing may result in malfunction or premature failure of components
in the system and, in specific cases, in voiding the warranty on the component.
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