Refrigeration Oils (Home/Commercial) What makes them so special/expensive?

[dehv]

From my understanding old R22/12 equipment used Mineral, which seems to mean non synthetic base 3 or less or Alkylbenzene base.

New R410a equipment seems to be POE in hvac and PAG in 134a/automotive, with R1234 using POE sometimes....
Apparently they don't mix well with non chlorine based refrigerants. But all work with propane (R290)

POE seems to be the defacto minimum standard (Polyol Ester?) Which to me seems like any synthetic oil would be up to snuff, Ester oils are just synthetic, right? additives aside?

My backyard refrigeration experiments with 410a/22 equipment running propane as retrofit (R290) lead me to want to just try using 100% synthetic motor oil in equivalent viscosity in place of POE.
What could possibly go wrong? Additives/etc wise.

Seems like emptying out the potentially moisture contaminated POE compressor oil and replacing with (Dry) synth motor oil would be better than trying to vac and re-use the old POE (clean looking) oil.

Thoughts/Opinions/Concerns? Other than the usual "UR DUMB DONT USE PROPANE" comments, speaking strictly lubricatively here.

Also, what exactly makes POE refrigerant oils so **** expensive compared to synthetic motor oil?

 

[frankbee3]

I am interested in your experiments. I haven’t ever had an air conditioner system opened up before so I can’t offer help with the lubrication questions.

My interest is which refrigerants are most efficient. I have always heard that propane is an efficient refrigerant.

I am guessing that in Canada, the POE lubricant may be better suited for cold flow than a mineral lubricant?

I was living in the hot desert when R-12 became hard to get and expensive. That is what drives my interest.

 

[frankbee3]

This thread may be of help to you?

POE oil (R-410a)

Some of the newer A/C or refrigeration systems use a synthetic POE oil ( R-410a ) . My understanding is the refrigerant dissolves better in the POE oil ? Anyone know of other reasons ? PAG oil is used in R-134a systems . For the same reasons . Anyone able to further enlighten me ? Can POE oil...

bobistheoilguy.com

 

[BMWTurboDzl]

From my understanding old R22/12 equipment used Mineral, which seems to mean non synthetic base 3 or less or Alkylbenzene base.

New R410a equipment seems to be POE in hvac and PAG in 134a/automotive, with R1234 using POE sometimes....
Apparently they don't mix well with non chlorine based refrigerants. But all work with propane (R290)

POE seems to be the defacto minimum standard (Polyol Ester?) Which to me seems like any synthetic oil would be up to snuff, Ester oils are just synthetic, right? additives aside?

My backyard refrigeration experiments with 410a/22 equipment running propane as retrofit (R290) lead me to want to just try using 100% synthetic motor oil in equivalent viscosity in place of POE.
What could possibly go wrong? Additives/etc wise.

Seems like emptying out the potentially moisture contaminated POE compressor oil and replacing with (Dry) synth motor oil would be better than trying to vac and re-use the old POE (clean looking) oil.

Thoughts/Opinions/Concerns? Other than the usual "UR DUMB DONT USE PROPANE" comments, speaking strictly lubricatively here.

Also, what exactly makes POE refrigerant oils so **** expensive compared to synthetic motor oil?

No 1: There's no such thing as 100% ester motor oil.
No 2: There's no crossover in operating environment between esters used in motor oils and that used in compressors/refrigeration systems.

 

[kschachn]

One wonders at your consumption of the proper oil such that price becomes a significant factor. Are we talking gallons here?

 

[4WD]

No 1: There's no such thing as 100% ester motor oil.
No 2: There's no crossover in operating environment between esters used in motor oils and that used in compressors/refrigeration systems.

I see the word ester dropped here allot - but not that %thingy …

 

[dehv]

I am interested in your experiments. I haven’t ever had an air conditioner system opened up before so I can’t offer help with the lubrication questions.

My interest is which refrigerants are most efficient. I have always heard that propane is an efficient refrigerant.

I am guessing that in Canada, the POE lubricant may be better suited for cold flow than a mineral lubricant?

I was living in the hot desert when R-12 became hard to get and expensive. That is what drives my interest.

The most efficient refrigerant seems to depend on application. Boiling point seems to be related to metering device sizing, so those with close boiling points seem to work best in retrofitting. A longer capilary tube/smaller orifice seems to mean lower boiling point temperature.

Straight propane didn't work in my van, I suspect due to the variable displacement compressor being confused by pressures, or because 134a's boiling point is only -26C, so I suspect the "12A" aftermarket cans are just blending butane (-12C) in to get to -26C blend.

R12 is -30
R22 is -41
R134a -26
vs
- 44c for propane (R290)

GWP aside, the only thing better/colder/efficient than propane, and holy grail in my opinion would be pure R32 with a boiling point of -52C vs - 44c for propane. This seems to be the new standard.
"R410A is a 50% combination of CH2F2 (HFC-32) and 50% CHF2CF3 (HFC-125)"



A couple projects I have on the go

1. Converting a 2.5T AC only working changeout lennox signature 410A condenser unit to heat pump by adding reversing valve, defrost board, crankcase heater and pan heater.

2. Heat pump water heater with guts from a 3/4HP rv ac unit.

3. Contemplating/Experimenting with window AC units installed backwards and controls bypassed as poor man's heat pumps. Issues with frost buildup are becoming evident, so i'm considering a defrost timer with heating element like in a fridge defrost, maybe a Chinese reversing valve install? Maybe split up the unit and put the evaporator in the crawl space as a dehumidifier?

Engineering ideas

Regarding hyper heat (getting capacity in lower outdoor temps) usually via done via vapor injection in OEMs to increase compression ratio;
Papers have shows success by a simple Hx between liquid and suction lines ("Economizer") just outside the condenser unit, which seems to help with AC loads, but for HP loads, one step better seems to me to:
- Install a heat exchanger in the always suction line (rather than externally) drawing heat from the liquid line just before the service valve inside the unit.
or
Install 25ft ish section of buried copper tube in the crawl space dirt (insulate above) and tee into the always suction line to increase efficiency and allow lower temperature operation maintaining capacity longer.

 

[CDX825]

Stick with actual refrigeration oil. Yes its expensive but you don't need a lot of it.

 

[dehv]

Stick with actual refrigeration oil. Yes its expensive but you don't need a lot of it.

Obviously, but why. Blind me with science.

 

[Tom NJ]

Synthetic motor oils are based on synthetic hydrocarbons which are not miscible with HFCs. POEs (yes polyol esters) are polar molecules containing oxygen and are miscible with all refrigerants. Most POE refrigeration oils have little or no additives and are ashless, as opposed to motor oils that usually have 12-20% additives and lots of ash. POEs are expensive because of the raw materials used to make them, which account for about 70+% of the manufacturing cost, but they work well.

 

[ARCOgraphite]

I wouldn't be experimenting with a flammable hydrocarbon refrigerant and lubricant in an automotive application.
I don't know much about the topic, but it just sounds wrong on the face of it.

 

[Snuckster]

I wouldn't be experimenting with a flammable hydrocarbon refrigerant and lubricant in an automotive application.
I don't know much about the topic, but it just sounds wrong on the face of it.

oh cool
something I am actually VERY familiar with
I used to have a 1968' Buick Electra had to mess with the AC system a handful of times due to age and an engine fire....speaking of which
guess what happened when the fire spread to the AC lines? a crack quickly formed making a sizeable blow torch followed by a BANG!
the flammability of the refrigerant doesn't matter all that much when the atomized oil in the system makes a breddy gud fuel air explosive on its own.

for clarity this happened with r12 and estercool in the system

fwiw the best results I had with converting the old r12 set up was using r152a AKA pic related

 

[dehv]

Thoughts/Opinions/Concerns? Other than the usual "UR DUMB DONT USE PROPANE" comments, speaking strictly lubricatively here.

FFS

 

[dehv]

I wouldn't be experimenting with a flammable hydrocarbon refrigerant and lubricant in an automotive application.
I don't know much about the topic, but it just sounds wrong on the face of it.

AND there goes the thread. not the point. I'm not even using in an automotive application.

Its R290 and used commercially in refrigeration systems factory without incident.

I'll be flushing the POE out completely along with all future propane related comments.

 

[dehv]

THREAD HIJACKERS, the issue is what additives or lack thereof, composition etc, make refrigerant oil what it is.

Thank you, TomNJ

 

[ARCOgraphite]

AND there goes the thread. not the point. I'm not even using in an automotive application.

Its R290 and used commercially in refrigeration systems factory without incident.

I'll be flushing the POE out completely along with all future propane related comments.

@dehv stated: "Straight propane didn't work in my van, I suspect due to the variable displacement compressor being confused by pressures, or because 134a's boiling point is only -26C ... ."

Well, that comment confused me. Is your van a reefer? My BIL is in distribution and trucking and has a yard full of them.

I tend to call out safety concerns if I smell any. - Ken

 

[kschachn]

THREAD HIJACKERS, the issue is what additives or lack thereof, composition etc, make refrigerant oil what it is.

Thank you, TomNJ

Thanks for joining.

 

[Billy_D]

From my understanding old R22/12 equipment used Mineral, which seems to mean non synthetic base 3 or less or Alkylbenzene base.

New R410a equipment seems to be POE in hvac and PAG in 134a/automotive, with R1234 using POE sometimes....
Apparently they don't mix well with non chlorine based refrigerants. But all work with propane (R290)

POE seems to be the defacto minimum standard (Polyol Ester?) Which to me seems like any synthetic oil would be up to snuff, Ester oils are just synthetic, right? additives aside?

My backyard refrigeration experiments with 410a/22 equipment running propane as retrofit (R290) lead me to want to just try using 100% synthetic motor oil in equivalent viscosity in place of POE.
What could possibly go wrong? Additives/etc wise.

Seems like emptying out the potentially moisture contaminated POE compressor oil and replacing with (Dry) synth motor oil would be better than trying to vac and re-use the old POE (clean looking) oil.

Thoughts/Opinions/Concerns? Other than the usual "UR DUMB DONT USE PROPANE" comments, speaking strictly lubricatively here.

Also, what exactly makes POE refrigerant oils so **** expensive compared to synthetic motor oil?

Mineral oils should never be mixed with R410a. Miscibility is one of the reason you don't add mineral oil to an R410a unit. The oil has to fully dissolve with the refrigerant. POE oils are also more hygroscopic than mineral oils. Hygroscopic oil tends to absorb moisture.

Here in the US you have to have a 609 EPA certification to be able to work with refrigerants. R290 is a bad and dangerous retrofit for R22 and R410a in residential applications. Here in the US only R470a has been approved as a retrofit for R410a.