Field test for Poe or mineral oil?

[Zahndkile]

I came across an interesting question on a heating and air conditioning forum that I am on.
Another member was in a situation where he needed to know if the oil in an air conditioning system he's working on was Poe oil or mineral oil so I was wondering if any of you know of a simple way to test whether it's Poe or mineral oil. I think it would be sufficient if we could just identify if there is some Poe present even if there is only 50% Poe I think that would be good enough.
My first thought was to mix it with water and test the pH or something because I know POE turns acidic in the presence of moisture but I don't know if that requires heat to turn it acidic or not.
I thought maybe y'all would have some useful input on the matter.

 

[Tom NJ]

Mixing with water will not breakdown a POE - takes a lot of heat and some catalyst or caustic. Refractive Index may be able to distinguish POEs from mineral oil. It would require some testing and calibration with a variety of known oils.

Portable refractometer

 

[Zahndkile]

Mixing with water will not breakdown a POE - takes a lot of heat and some catalyst or caustic. Refractive Index may be able to distinguish POEs from mineral oil. It would require some testing and calibration with a variety of known oils.

Portable refractometer

Thanks. I actually just read about oil refractometers. That should work especially if he knows what the potential oils are.

 

[Fitter30]

Don't think there is one. Would have to send it off to a lab. There is to many types of oil. Larger compressors have means to change oil in them. 10 hp and up. Won't get a complete change with one change. Refrigeration systems and as fast as refrigerant are changing the oils are to. 1970 five refrigerants mineral oil with a few viscosity. Now can't even count refrigerates between all the replacements, blends , propane, and all the chemical companies with their greenhouse neutral gases.

Mineral – a by-product in the distillation of crude oil to produce gasoline. Mineral oil can be classified into the following groups: naphthenic, paraffinic, and aromatic. Naphthene-based mineral oils are suitable for refrigeration systems using CFC or HCFC refrigerants.

Alkylbenzene (AB) – is a synthetic oil suitable for refrigeration systems using CFC or HCFC refrigerants. It is compatible with mineral oil and compared to mineral oil, it has improved refrigerant miscibility with R-22 at low-temperature conditions.

Polyolester (POE) – the primarily synthetic oil for refrigeration systems using HFC refrigerants. It is also suitable for refrigeration systems using CFC, HCFC refrigerants and being evaluated in CO2 systems.

Polyalkylene Glycol (PAG) – a synthetic oil primarily used in R-134a automotive air conditioning systems. It is more hygroscopic that either POE or PVE oils, but it does not undergo hydrolysis in the presence of water.

Polyvinyl Ether (PVE) – a synthetic oil that is being used as an alternative to POE oil. It is more hygroscopic than POE oil but less than PAG oil. Like PAG oil, PVE oil does not undergo hydrolysis in the presence of water.

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