White foamy oil?

[marc5180]

Is there a reason why you get white foamy oily substance sometimes when connecting gauges. It seems to happen on the older R22 systems.
What causes it? Is it when the sytem is short of refrigerant which causes the oil to heat up and foam or even when moisture is in the system?? or something else

[GreenFly]

White foamy oil substance is caused by liquad refrigerant boiling off in the oil and the formation of this oily foam is the result of the boiling off of the refrigerant, I belive that it is more evident in Mineral based oils used on R22 systems, but then i could be wrong.

[chemi-cool]

GreenFly, you are absolutely right!!

[icecube51]

on bigger compressors, like the copeland semi's, you can see the foam in the control oil glass, and its like Greenfly explained, but not only the R22, but on every refrig.

Ice

[Brian_UK]

You might also find it due to the system being a little short of gas which is the reason you probably put the guages on in the first place.

Lack of gas = less gas to carry oil around system = oil settles out near tees, branches etc.

That's my theory anyway.

[NoNickName]

Recently I came across a batch of R134a from a world known company which causes flocculation in POE oil at low temperature. Flocks are like white flakes, floating around... they may clog the oil passages if oil is not properly warmed up.

[marc5180]

Good stuff another one for the memory bank. Thanks guys