Freon 134A Why Does it Burn?

It is not flammable under normal conditions.

Don't listen to your friend.

MATERIAL SAFETY DATA SHEET (MSDS) R134A ... - Afrox

LP gas as a replacement refrigerant is a no no.....It is illegal and dangerous...

http://www.lpgasmagazine.com/epa-investigates-use-of-propane-as-refrigerant-substitute/

Co2 is already used as a refrigerant...but is not a drop in replacement...

http://www.achrnews.com/articles/94092-co2-as-refrigerant-the-transcritical-cycle

Why does wood burn? Why does gasoline burn? How high is up?

What is R-12A? R-134a is sort of a replacement for R-12. LPG (basically propane) is already known as R-290. I don't know what the R-22a designation is all about, unless it and R-290 are close in properties; but even so, that is confusion on a popsicle stick.

Propane is a 100% drop in and go alternative to R-22 so for a while it got listed as R-22a to ease confusion about whether or not it was a direct R-22 replacement.

As far as its actual legality it is legal to use in most any stand alone cooling system that does not have a heating function built in. Many commercial refrigerators and freezers you find in grocery stores and warehouses use it.

It's also legal for anyone to buy as well and you can find tons of it online like on eBay and Amazon and such.

There is a non-odorized propane, I think called HD5, that was once (and maybe still is) used for catalytic oxygen removers in controlled-atmosphere storage systems. Does the refrigerant need this, or can it use the same propane as sold almost everywhere?

Brings to mind the question: Do HD5, R-22a or R-290 have the mercaptan odor added? If there was a leak would a bystander know it?

"There is a non-odorized propane, I think called HD5, that was once (and maybe still is) used for catalytic oxygen removers in controlled-atmosphere storage systems. Does the refrigerant need this, or can it use the same propane as sold almost everywhere?"

No they do not but under typical leak conditions the likelihood of the refrigerant building up to it's minimal A/F ratio is incredibly small being typical refrigeration leaks are not explosive decompression of the system but rather microscopic leaks that can take days to years for a system to bleed out to the point of not functioning properly.

Even on a very fast leak that takes a few days to bleed a system off the actual rate of leakage is similar to the gas vapor release that any common butane type lighter produces and if you have ever tried to capture the gas from one of those to deliberately get a explosion or even a basic flame burst you would know how hard it is to do in a controlled environment let alone an environment of regular high airflow.

Sure it's possible for a leak to start a fire but statistically the gas mains feeding natural gas or LPG from a bulk take outside the structure are magnitudes or order more likely and common. As for being a rational concern you have the option of simply not using it but that said if you are that concerned about the potential for a fire from combustible vapor you should seriously be concerned about the volumes you directly expose yourself to every time you fill up one of your own vehicles.

And yes the stuff in your 20# cylinder under your BBQ grill works pretty well!

Thanks. I agree with you. The flammability issue seems minor; after all, a barbecue is flammable, and hardly anyone worries about it. I think some European refrigerators use isobutane as a refrigerant. The odorant bit was just curiosity.

Personally I would prefer that things like flammable refrigerants have some sort of scenting agent in them that makes any degree of leakage detectable to the average nose.

I believe that propane and other such flammable refrigerants are used far more every where else in the world than they are used in the US.

Back in high school R-12 was taken off the shelves and the common work around for that was what I always heard referred to as a 'Mexican Conversion' wheren the R-12 was simply vented off and what ever was under your BBQ grill went in!

I suspect that back then there were hundreds of vehicles along with countless farm tractors and heavy machinery units in the late 80's to early 90's in my area that got 'Mexican Conversions' when cheap off the shelf R-12 disappeared.

I know it was what I first learned about refrigeration on!

Fill to 90 - 110 PSI above ambient temperature on the high side or until the low side gauge reads about 28 - 40 degrees F as if filling the system with R-12 and enjoy your frosty cool AC! If you smell propane stink follow your nose and fix the leak then refill again.

That was the standard instructions that came with Mexican Conversion kit.

"The flammability issue seems minor"...

Really, do you run your barbecue in the house? Have you ever seen a lp gas explosion?

Okay what about those of us and possibly yourself that have natural gas or propane feeds the run through the walls and floors of our houses to feed our furnaces water heaters and cook stoves?

How much gas do you suppose those 1/2" - 1" lines plastic line they use now can feed if they burst open due to your primary pressure regulator failing and sending the typical 20 - 150+ PSI that goes into them into those plastic lines that are rated for less than 5 PSI? ? ?

Or for that matter how about all those spray cans your wife has in the bathroom? How many of those are highly flammable plus hold a pound or more of highly contents?

Or what about that storage closet/cabinet that has all those cans of flammable spray paint, cleaners, 1# propane bottles for your camping stoves and what not?

Or those plastic fuel jugs you have in your garage and or sheds? Do you have any idea how easy it is for a hot peice of metal given off by a spark from who knows what can melt through one making it leak?

Given everything else around our homes that is highly flaible plus deliberately sprayed into the air inside our homes the 2 - 4 pound of propane that would be well contained inside a sealed system designed to work at high pressures and temperatures seem pretty inconsequential and minor to me.

I'm actually for safety more than most people but I am also rational about what is of valid concern and what is not and a few pounds of propane contained in a sealed system designed specifically to handle high pressures and temperatures on purpose does not concern me the least.

My wife and daughter in our small bathroom emptying a half a can or more of highly flammable hairspray and who knows what else in there over a 10 minute period while constantly firing up hair dryers and curling irons and whatever else they have that has no explosion proof design.... Well yea I am rather surprised I don't have two burn victims and a missing wall by now.

I guess neither one of you has ever seen a catastrophic failure of a compressor at the wiring terminal... .I've actually seen one split wide open...Having the wiring terminal burn out is a very common occurrence...

https://www.youtube.com/watch?v=ngazoUgGpDY

I've scrapped many a AC systems over the years ,with torches and plasma cutters, and I can say for certain that although the refrigerant may not be flammable most systems oils when prayed out in a fine mist under pressure or just heated up hot enough by an open flame or electric arc sure are!

You want odorant? Go back to the old ammonia charged cooling systems. That has an odor. In the bad old days when electric skillets had the 120V prong exposed when removed, I know someone who managed to drop one on an old ammonia charged refrigerator coil in a basement apartment - fun!

You're a little fast and loose about regulations...any property damage or injury to persons resulting from the use of unauthorized refrigerant would leave you legally responsible and liable for any damage, not to mention denial of any compensation from any insurance coverage and possible fines and jail time, then you would have your own conscious to deal with if death or serious injury were involved....it's just not worth the risk...

"EPA says it has not approved the use of propane refrigerant or other hydrocarbon refrigerants in any type of air conditioner. Homeowners and technicians are strongly recommended to limit use of propane or other hydrocarbons to only those appliances specifically designed for these substances and that are properly marked to alert technicians that the equipment contains a flammable substance, the agency adds.

EPA has approved the use of propane as a substitute refrigerant for R-22 in industrial process refrigeration systems and in new, standalone retail food refrigerators and freezers that are specifically designed to use flammable hydrocarbon refrigerants."

I never said it was allowed in central AC systems or at least not without special labeling and or other considerations in place first.

I said it is used in many standalone type refrigeration systems like what are found in commercial environments just as your bold print specifies.

As for private residential applications window AC units and dedicated heat pump systems are allowed to use R-290 /R-22a provided local ruling allows it or if it's your own system and you take full responsibility for your usage of it.

I know how this game is played too or at least what flies in my area.

These are national laws....you do live in the US don't you....?

Yes I live in the US and yes I am familiar with the federal laws. I am also familiar with their loopholes and grey areas too along with the concept of using rational sense and reasoning when working with potentially dangerous substances.

I for one do not let what if and every remotely conceivable concern keep me from doing things though either.

If something needs special permits and or training I will get them but if they don't for whatever personal work I am doing I am not going to bother with it. Read, re read, consider what may happen and go from there.

you could always inhale some 717

RE: the CO2, R 744, it is not a direct replacement. It has some amazing properties but it is a high pressure system, for example at 80 Degree F you are looking at about 950 PSI so all components will have to be much more robust. Other properties is the compression to elevate captured heat is about 3:1 and heat can exceed 250 F. It boils at -78F so will pick up heat easier than freon and others that boil at -40 F. I suggest you wait until 2018 at that date all European vehicles will be on R744 (CO2) by law. You should be able to tap into this technology quite easily. These vehicles will have immediate cockpit heat due to the CO2 system. This came about in crash testing where alternatives burst into flame but CO2 of course does not burn.