AC with Propane- Staying Alive - Page 8 - PeachParts Mercedes-Benz Forum

CWW · #**106** 08-18-2009, 08:42 AM

Quote:

Originally Posted by mercmad6.3

I dispute the fact that Australian taxi's are using propane ( LPgas here)but they probably are as corruption is a way of life here.
Several million cars per year are sold with propane/butane mix in the air con.
R134a is due to be banned.
But for some facts.
propane only burns when it is pure. Add a fridge gas such as remnant 134a or R12 and it will not burn.
It will create it's own oxygen when it does burn creating a cycle of burning and oxidizing.Fireman the world over have been taught this.

Have any of you experts ever burnt R12?
What is the gas given off?
It's phosgene ,it's green and it kills you.
I have had a whiff of pure phosgene,hence the fact i have half of one lung missing.
The effect is instaneous and literally takes your breath away.
If you are in car accident and there is fire the burning R12 will kill you,leaving your corpse to burn .

But the Question I am asking is "How on earth are you guys getting Freon"? ,it has been banned for at least 15 years and the US was supposed to be leading the way. The Chinese have been condemned for making the stuff outside of international agreements.
I have been using LP gas for at least 18 years in all sorts of Fridge plants with zero problems .

As with everything illegally made in China, it eventually finds its way over here whether it's supposed to or not.

I've bought R12 myself and when I arrived I noticed the cylinders were waaaaaaaaaaaaaaaaaaaay too new to have been produced in the 80's. Maybe a few months old at best. But hey, I'm one of those folks that learned pretty early on not to ask questions you don't really want to know the answer to. It works, and I'm happy. End of story.

roedel · #**107** 08-18-2009, 10:16 AM

Propane or LPG (liquified propane gas) works much better than R12.

Some LPGs brands sold are a mixture of propane and butane but some are pure propane.

@mercmad6.3
nobody claimed that R12 is any good thing in this thread.

Propane is the way to go and yes pure propane works fine in some Ac's as if the system can handle the pressures
.
Pure Propane=R290 it is sold as an replacement for R22 brandname HR22 from Hychill. But i am sure you are aware of that.

roedel · #**108** 08-22-2009, 09:38 PM

So i received my hydrocarbon gases, one bottle of R290 one bottle of R600a, superdry and 99.9% pure.
Mixed the following blend:
37% R600 (isobutane) + 63% R290(Propane).
The pressure of the blend at 86 deg F (28deg C) is at 104 psi.
Remark pure R290 propane has a pressure of 135 psi at the same temperature, adding 37% of R600 is reducing the pressure by 30psi.

I filled my Ac with 11.28 ounces (320 gram).
The LS400 usually takes 35.2 ounces (1000gram) of R12 gas.

I could load the complete batch in seconds, without starting the engine.
I started the car, the compressor kicked in, it sounds super smooth, the noise is more like a hisssssss than that grrrrrrr noise i had before, due to the fact that the propane molecule is much bigger than the R12/R134 molecule, thus easier to compress.

My pressure readings: Low side 38psi, High side 150 psi.
With the R12/R134a blend i had 40psi/220psi.

Gotta check out why my low side readings are on the high side in either case, but i belief it is because of the gas mix.
The Lexus specs for R12 are 21-28psi low and 206-213 high.

I am getting a instand duct temperature of 53 degF (12Cels) on a 90 deg (33Celsius) super humid day. The condenser is not only dripping, water was running out the drain hose, i could fill a small coffee cup in about 1.5 minutes.

Once i put the system to recirculation the duct temp drops to 44 degF (7Celsius).

The performance of the system is exactly what i had with my high performance R12/R134a mix, but with much less strain on the compressor, the changes in pressure and compressor noise are obvious.
Not to mention the amount of engine power saved with the mix.

Another thing i noticed, when i switched on the AC at idle with R12 my idle Rpm was noticeably dropping before being raised by the ECU.
Now the idle RPM do not drop.

Propane is the way to go!