use liquid petrolium gas instead of R12 ???? - Refrigeration-Engineer.com forums

guestingmale · #1 07-12-2002, 04:07 AM

hi
It is stinking hot in Australia and going to get worse as we go more into summer.
My car air-conditioning is far from cold.
There are no leaks. The system has probably got too much moisure trapped in it , for one thing.
I have not replaced the receiver drier nor the R12 gas for years. As R 12 is no longer availabe. My main question is.
Can LPG ( Liquid Petrolium Gas) be sucessfully used as a replacement as the gas. Is it almost as good as R12. Will it be detremental to the compressor or other components.
It is very cheap compared to the current gas available now.

thanks
Chris

Prof Sporlan · #2 07-12-2002, 05:37 PM

LPG is going to be either propane or butane... neither well suited as an R-12 replacement. You're better off finding on of the many R-12 service replacement blends available. You might find this link of use: http://www.epa.gov/ozone/snap/refrig.../macssubs.html

guestingmale · #3 14-12-2002, 02:29 AM

thanks for your reply Prof Sporlan,
Yes it is propane.
I have read the info you pointed to.
I will go with the widely accepted replacement for r12, even though it will not be as efficient.
bye

**Argus** · #4 16-12-2002, 12:04 PM

You may care to check out the local laws in Assie.
I seem to remember reading (in Celsius magazine, I think) that hydrocarbons are banned in car A/C. I don't know what they do to you if they catch you using it!
Does anyone know if it's true or not?

Levin · #5 27-02-2003, 05:41 AM

It is better to use R134 a then propane. Propane in your case will have very high condensation pressure. I have had experience to transport the liquefied propane on LPG/C and I always use the two stage reliquefaction plant.

fridgefixer · #6 27-02-2003, 08:15 PM

R134a must not be used in a vehicle that originally had R12 as its refrigerant with out a full retrofit of the compresser oil, seals and in some cases the the hoses.R12 uses mineral oil and R134a uses synthetic the two cannot be mixed or else you will have compresser failure as the 134a will not carry the mineral oil around the system.There is however a way, use Isceon 49 (R413a) as a direct replacement for the r12. R 413a is a mixture of R134a and isobutane which is the component that will carry the mineral oil around the system.I have used it in hundreds of vehicles with no problems good luck.you also need to charge around 10 % less than the original r12 charge ie original r12 charge 1100grams r413a charge 1000grams

Karl Hofmann · #7 27-02-2003, 09:07 PM

Isceon 49 (R413a) does work pretty well on later R12 vehicles (1993-1995) because the manufacturer had already fitted the vehicle with barrier hose and a drier with a dessicant to suit the incoming R134a. Earlier cars may still have a problem with R413a (The main component is R134a) because of the lack of barrier hose and suitable dessicant. You may also find that the reduction in performance, when you change refrigerants is not acceptable to you, in which case changing the condenser from a serpentine type to a parralell flow design will help. Fortunatly we do not have this problem in the UK as high ambient temperatures are rare and many cars that use R12 have rusted away. If the car is worth keeping shell out some cash and do a full retrofit, if its a banger R413a will do, If you intend to use HCs then dont forget your asbestos shorts!

As a point of interest HC's are banned for automotive use in the UK, EU and 18 states in the US, though I get the impression that they are permitted in Austrailia. Not too sure what they'll do to you if your caught with HC's in your car, but I'm sure that you'll get a good grilling

guestingmale · #8 28-02-2003, 11:29 AM

thanks
Argus, Levin, fridgefixer and Karl Hofmann

Yes HC's are banned here in oz too.
Interesting reading fridge fixer and karl.
I am almost through the hottest part of summer, and having a good look at the car, lets call it a banger in good condition.
R413a is the go.

Thanks again fellas

750 Valve · #9 01-03-2003, 09:13 AM

You're right about 413a, you can bang it in your temprite system too, next best thing to R12 if you got the condenser to cope. Dont know about these summers, seem to be getting hotter! Bring on some cool weather, can turn all those sprinklers off under old condensers!!!

Robearbam · #10 10-03-2003, 07:01 PM

I always wondered how the mustache was invented!

abcdefg1675 · #11 12-03-2003, 01:19 AM

Can Pure propane be used in an R12 system for those of us who have scored an old fridge with kinked up lines for free?

Karl Hofmann · #12 12-03-2003, 10:06 AM

If we're talking automotive, keep the propane for the BBQ. R12 is still available in the US.

aenigma · #13 13-03-2003, 09:51 AM

Quote:

Originally posted by abcdefg1675
Can Pure propane be used in an R12 system for those of us who have scored an old fridge with kinked up lines for free?

Yes it will work fine for that application.

abcdefg1675 · #14 14-03-2003, 03:20 AM

I would leave my fridge system alone, but the evaporator is one of those tin boxes with the evaporator channels milled into the walls. Completely useless for super-cooling a computer, but nice for a cheap mini-fridge.

What oil will i need? The condensor i will use is an old evaporator from an R12 system on an old toyota. the oil that dripped out of it is a pinkish color, and feels like 30W...

For my evaporator i will probably get a hunk of steel 3" thick, carve a channel through it and weld it to another 3" hunk of steel.

Gary · #15 14-03-2003, 01:44 PM

Quote:

I would leave my fridge system alone, but the evaporator is one of those tin boxes with the evaporator channels milled into the walls. Completely useless for super-cooling a computer, but nice for a cheap mini-fridge.

I would start with a fridge system because the components are designed, sized, and matched for low temperature operation. In particular, the cap tube is matched to the compressor, which is extremely important.

Quote:

What oil will i need? The condensor i will use is an old evaporator from an R12 system on an old toyota. the oil that dripped out of it is a pinkish color, and feels like 30W...

Automotive motor oil contains wax, which will gum up your system like you wouldn't believe. Don't even think about it. The proper refrigeration oil depends upon the refrigerant used. They must be compatible.

Quote:

For my evaporator i will probably get a hunk of steel 3" thick, carve a channel through it and weld it to another 3" hunk of steel.

Is there some virtue in doing everything the hard way?

abcdefg1675 · #16 15-03-2003, 12:31 AM

right now, all the money i have is a dime. And this cooling system will be put in an old computer case and the evaporator will be bolted onto a cpu. Id rather have someone mill out a channel through some steel than buying an overpriced promentaria system.

What oil should i use for propane, if i use the old cap tubing from the fridge?

aenigma · #17 15-03-2003, 09:33 AM

Well your compressor should already have oil in it.If not you can get refrigeration mineral oil for it.
As far as the evaporator goes, don't mill anything out of steel, just make a basic hollow evaporator using copper pipe and pipe end caps.Can be made in a few minutes and very cheap.

abcdefg1675 · #18 15-03-2003, 06:44 PM

This propane refridgeration system is going to be used to cool water, for computers or whatever. I need a steel block or something of that size to bolt on my slot A cpu, or i could make one that fits on it and run an anti-freeze mix through it.

Ill either take some 1/4" copper piping and heat it up with a torch, then make a few loops over a steel plate and solder the copper pipe to that.

Can someone with MSN messanger add me to their list so i can get some help with putting together my propane system? abcdefg1675@hotmail.com

**Dan** · #19 15-03-2003, 09:27 PM

Quote:

Is there some virtue in doing everything the hard way?

Hahahaha. Classic Garyism. Too funny!

abcdefg1675 · #20 16-03-2003, 05:02 AM

i have to do everything the hard way. The only powertools i have are a chain saw, 1.8hp weed-eater with 6" saw blade

, aincent 1970's jigsaw thats seized up, and a single speed (on or off) 1/4hp drill. for hand operated tools i have screwdrivers, crow-bar, hammer, sledge hammer (my all-time favorite) and a hack saw.

aenigma · #21 16-03-2003, 09:04 AM

Ok for the waterchiller you want to use copper pipe, I like using 1/4 as it is easy to bend into position.
For the evaporator do not use steel, steel is a poor choice for heat conduction.Like I said, use copper pipe and pipe end caps, it is very cheap and will work MUCH better than a steel plate with copper pipe soldered to it.
Just get a length of 1" pipe and cut it down to size(like 1 inch tall or so) and get 2 pipe caps for it, cut one cap down to size and then drill a hole in it and screw in a flare fitting.Now you have a cheap direct die evap(only use it if your computer is laying on its side).

http://www.subz3ro.net/block.jpg
http://www.subz3ro.net/block2.jpg

Piece of cake

**frank** · #22 16-03-2003, 11:56 AM

Keep the hammer handy for use later on in the project

abcdefg1675 · #23 18-03-2003, 01:50 AM

I could take the copper pipe, bend it into many S shapes, and solder/weld another couple S shaped loops onto that, and have antifreeze mix run through that.

aenigma · #24 18-03-2003, 07:57 AM

Yes but that is an awful lot of work don't you think?You could easily put that copper pipe in a very small res.

abcdefg1675 · #25 19-03-2003, 06:16 AM

i have no other way of doing things. The only money i have is that dime i saw a few days ago when i was cleaning my room... My love, craving and addiction to mountain dew has put me in the "poor house"...

aenigma · #26 20-03-2003, 09:44 AM

Uhm well the ways I am suggesting would be cheaper and easier.

abcdefg1675 · #27 21-03-2003, 06:13 PM

now i have to dig my refrigerator out of a snow bank...

abcdefg1675 · #28 21-03-2003, 06:16 PM

because of the higher condensation pressures of R409a, would this cause pre-mature faliure of my 30 year old compresser?

Gary · #29 21-03-2003, 06:33 PM

The nightmare scenario would be running the computer without the cooling system, building up lots of heat and pressure, then start the compressor.

In fact, this would be a very bad idea even with the lower pressure refrigerants. The cooling system should be COLD before the computer is started.

abcdefg1675 · #30 24-03-2003, 05:39 AM

Well, of couse i will let the thing cool down, but this "refridgerator" inside a computer case wont just be for cooling my computer. I probably will have two metal 1/4" pipes sticking out a few inches so i can hook up regular tubing. I could run it through a ford pinto heater core i have sitting here for a crappy airconditioner... I have a HV inverter i built and it gets hotter than hell... gave me a 2nd degree burn

Gary · #31 24-03-2003, 06:19 AM

LOL

I don't know where to begin. Just sitting here shaking my head.

**frank** · #32 24-03-2003, 08:36 PM

Still can't wait for the book to come out

**Dan** · #33 25-03-2003, 01:53 AM

Quote:

I don't know where to begin. Just sitting here shaking my head.

You left out "smiling."

abcdefg1675 · #34 31-03-2003, 02:30 AM

i dragged home the refridgerator guts, along with an airconditioner unit out of a hotel room (its very big and VERY heavy). I plugged in the refrigerator guts. At first, it made a puffing sound like a small animal sneezing quickly. after a minute, the pressure buit up and i started hearing the freon spraying in the evaporator. I left to spray out the aincent airconditioner, came back and the compressor was rattling, not loud but annoying. The condensor wasnt hot at all, and the evaporator was slightly cool.

angryk · #35 01-04-2003, 01:04 AM

plugged in refrigerator guts?

abcdefg1675 · #36 01-04-2003, 05:50 AM

yes. The compressor, the receiver thats hooked to the capillary tubin which is hooked to the evaporator, which leads back to the compressor which also has a 120v cord on it. I plugged it all in, let it run for nearly 1/2 hour. The condensor was cool, the evaporator was about room temperature and was hissing loud. The compressor, well, burned my hand to the touch. And when i tried to plug in the compressor it seemed to be hydrollically locked. I had to heat up the condensor with a hairdryer before the compressor would think about twiching around and start running. I dont know if this means the refridgerant has been evacuated out. It shouldnt take 12 minutes of run time before the evaporator starts to make the hiss sound.

i dont want to open up the weird service port thinking theirs nothing in it and letting out 50$ worth of R12, but then again i didnt pay a dime for it.

does this sound like the refridgerant had been evacuated, then someone didnt do a good job of sealing it back up and air leaked into the system?

**frank** · #37 02-04-2003, 06:37 PM

Make a note of that - always take a hairdryer with you to heat up the condenser!!

abcdefg1675 · #38 03-04-2003, 01:26 AM

also dont follow the order of my message. I plugged in the compressor and had to heat up the condensor before it ran...

Its never done this before. Last year it started up after a few tries, but now its binding up. I dont know if its from being evacuated and the high vaccume is too much for the compressor, or the valve thing thats hooked to the condensor (gotta love the tech-terms) isnt fuctioning and the compressor is full of refridgerant, but it doesnt seem likely that it has refridgerant in it if the compressor burns your hand, and the condensor is colder than the evaporator... sound good?

also, can i cut my cap tubing in half and use it like a dual sprayer system? My aincent hotel room airconditioner has two large cap lines going to the evaporator, and one very big return line. The condensor is about 1/2 the size of the evaporator... im not sure why. It seems it should be the other way around, but if it works...

see, the other main use for my portable refridgerator in an old computer case will be cooling my 500 gallon swimming pool. Its nothing like coming home to a pool thats 90 degrees. Ive set a thermometer in my back-yard. after i came back home (a few hours later) the temerature reading was 115 degrees. I set the thermometer in the full sunlight on my fence and many hours later the reading was 120. Now, i have this 120v water pump from a washing machine that i could use to circulate hot swimming pool water through a waterblock and keep the pool cool.

abcdefg1675 · #39 10-04-2003, 06:14 AM

that 1/8hp compressor isnt up to the job of condensing propane. I pulled a compressor from an 8000btu airconditioner.

copy and paste the following links into your browser. Geocities wont allow you to access these files outside of their website... as the old saying goes "you get what you pay for"

http://www.geocities.com/kylehus/compressor1.jpg
http://www.geocities.com/kylehus/compressor2.jpg
http://www.geocities.com/kylehus/compressor3.jpg

notice on the top of the compressor where the wiring cover was, theirs a thing, with a metal coil on the outside of it. im not sure what it is. does anyone know where to hook the 120vac in, and where to hook the 25uF capacitor to the 3 wires? theirs 9 possibilites... i know the wiring for this compressor is just like any other.

Gary · #40 10-04-2003, 02:37 PM

Start here:

http://www.refrigerationbasics.com

abcdefg1675 · #41 10-04-2003, 08:03 PM

re-reading stuff i already know isnt going to help. I didnt mention what brand the airconditioner was. Its a carrier R22 unit.

Gary · #42 10-04-2003, 08:40 PM

Yes, we can plainly see how knowledgeable you are. Pardon the interruption. Carry on.

**Andy** · #43 10-04-2003, 09:07 PM

Hi abcdefg1675
you are what I would commonly describe as a fool. You are going to hurt either yourself, or someone around you.

Stop what you are doing now, whilst you still have all your body parts, and some dignity.

Regards. Andy

herefishy · #44 10-04-2003, 11:29 PM

LOLOLOLOLolololololololooooooooohhhhhh!!!!!! fart, giggle,..... snort!

This is absolutely so funny, that it could only be composed by the most adept and experienced field technician that ever existed, with a wonderful talent for use of the English language, in context !!

Gary · #45 10-04-2003, 11:45 PM

I swear, herefishy. It isn't me... LOL

herefishy · #46 11-04-2003, 12:25 AM

Quote:

Originally posted by Gary
Yes, we can plainly see how knowledgeable you are. Pardon the interruption. Carry on.

Gary, You are too cool for school!

Gary · #47 11-04-2003, 12:42 AM

Quote:

Gary, You are too cool for school!

I've always thought that, but Mom made me go, anyway... LOL

abcdefg1675 · #48 11-04-2003, 01:48 AM

this has turned into a damn soap opera. Im only 16, what do you expect out of me?

carriers website doesnt have anything for a wiring diagram for this old compressor. I just guessed at where the capacitor and 120vac would go. After about 3 tries, i had made 1cm of the 12AWG wire explode, and had to re-solder. When i finnaly had gotten the compressor to run, i was suprised at the displacement of it. It builds up enough pressure, more than enough for propane.

I have all of the cap tubing i will ever need, now i just need to buy a new dryer and a service port, and build my own adaptor so i can charge up the condensor unit with propane.

Now, what is so dangerous about this project aside from the propane? you think i am not apt to solder piping, and screw on a few charging adaptors? i didnt have a problem building my 1200W herf...

( although i am afraid to use it... )

Gary · #49 11-04-2003, 02:08 AM

Quote:

this has turned into a damn soap opera. Im only 16, what do you expect out of me?

I expect you to do your homework.

The problem isn't that you don't know. The problem is that you don't know that you don't know. That's dangerous.

My impression is that you want to know without learning; You want to be there without getting there; You want to leap to the finish line.

It's the little details that you are not aware of, and the misconceptions/assumptions you make in order to fill in the gaps in your knowledge that will hurt you.

Your statements thus far have been loaded with misconceptions and assumptions, such that we would have to unteach you and start from scratch.

abcdefg1675 · #50 11-04-2003, 03:07 AM

I only know what i know from reading refridgeration and airconditioning traning manuals (old ones). I bet money that if anyone here started out with just knowlede with electronics, read a few of these books, encyclopedias, and have only repaired and overhauled a fridge and 3 airconditioners, and one car AC system they wouldnt know much about how to do what im doing.

if you expect me to do homework, were you referring to that website? if so, their is practically nothing there that is usefull. It talks about how the refridgerant makes its way through the system and has a drawing of the compressor.

and dont tell me i dont know when i dont know, i know what i dont know, like matching cap tubing sizes to compressors, and different types of oils, nor do i know how much refridgerant to put in. I will use some pressure gauges, and use the temp/pressure method.

The only reason that i am using propane is because others are too expensive or unavalible. R134a is $11/lb at wall-mart ( a big rip-off) R12 is about 60$/lb here, and you have to hire some bum to evacuate the system and charge it up for the same price at which i could buy a new condensing unit with an external evaporator. R22 is $7/lb, but they wont tap the 30lb can and sell you a few lbs. its either all, for 200 and something $ + tax, or nothing. also, someone has to charge up the system for you, because of EPA regulations, and you cant keep the left-over R22. Propane is avalibe at just about anywhere, even goodwill

.

Propane is 1.09$ per pound (the propane without butane mix, or stink additive). Ive talked to a few people who have done this R12-propane conversion without any modification. Their old freezers seem to work fine, but its not a matter of if it works or not, but how long it will last. I have a compressor that isnt too old, has been tested on the high-side for 350psi (before the thing breaks).

i have the cap tubing thats been matched to the compressor (R22, at 20 degrees F). One thing that i dont know is the efficency of propane, what the evaporator temperature would be without a load using this cap tubing, or how long the compressor will run with the high pressures.

also, i dont know what oil to use. The compressor used to have the "green stuff" in it (another very technical term commonly used) When i was using the fail-safe guess and chech method, the compressor started up. The lines were pinched, pressure built up in the compressor and it sprayed out all of the oil into the air.

and what exactly is the name of the "green stuff"?