I have a 91 ford ranger with a 3.0l V-6 engine.

I changed the a/c line on the compressor,it broke and shot freon all over me (R-12)– I changed the line,and cleaned all parts with denatured alcohol like I was told to do,I also replaced the drier,pressure switch and all "O" rings in the entire system,I bought a new compressor and shrater valve…Rented a vac.pump,pumped it down and recharged it with (R134 and ester 100 oil)—-It blew 39 degree air from the vents for 2 days then the a/c compressor locked up and burnt the belt off..What did I do wrong here?I would like to attempt it again,but it is expensive trail and error,What should I do next attempt to have great a/c like I did before?

I’ve Been doing a lot of bodywork lately and run a 6" da sander I think it’s rated at 10 or 13 cfm and my craftsman air compressor just can’t keep up. I have an industrial baldor motor that’s 2hp 1725 rpm it’s a 00 motor according to baldors site and it runs smooth and great. Do you guys think I can use that motor with the compressor I have? Or should I get a bigger 2 cylinder compressor? (by the way I have two I’d say medium sized tanks that are tied together) if I need a new compressor for that size motor what type should I get (best for the price I’m sorta on a budget)

Hi. I gather that the temperature is measured in degrees Kelvin for these matters, with 273 K being 0 degrees C. So that a temp in degrees Celsius plus 273 = that temperature on kelvin’s scale.

Also, It seems that the ideal gas law rules the relationships between the temperature, pressure and volume of any gas or any mix of gases as long as no phase change occurs, as in condensation of one or more constituents, and as long as no chemistry takes place. Nothing burns for instance. OK, I think I get all that.

But if that much is true why doesn’t "shop air" from any air compressor condense to a liquid as it comes out? As the gas (air) is squeezed to ten times atmospheric pressure its temperature shoots up to ten times hotter. That’s *2460* degrees Celsius if the air starts at 0 Celsius. That’s actually 273K raising to 2730K, but whatever. OK?

Of course heat flows from higher temperatures to lower and so the air compressor gets hot without the air within ever getting anywhere near 2460 C. And the compressor has a heck of a lot more mass than the air being compressed, so that it doesn’t get anywhere near 2460C either. And even then "specific heat" is more complicated than just a difference in density. Well OK. Not an issue here, or is it?

Here is the part I just can’t fathom at all; If the compressed air is at room temp, say 0 C, and it’s allowed to go from 150psi down to the 15psi of the atmosphere, then what keeps the expanding air from just liquefying?

The Ideal Law seems to predict that the room temperature (0C or 273K) air at 150psi should drop to 1/10th that temp at 1/10 the pressure. That would make it 27.3 degrees Kelvin, and that’s almost cold enough to liquefy hydrogen. Now I’ve never seen anyone hook an expansion (rocket) nozzle onto an air line but even without one it seems like at least the CO2 should condense out.

I’m pretty sure my reasoning and/or information must be flawed but I can’t figure out where the train jumps the rails. Can anybody please point out the obvious to me or should I just make a nozzle and see what happens? Is that how they make dry ice?

Anyway, Thanks.

I moved my mobile home and the guys who were working on it cut the lines and let all the freon out and did not seal the lines. It sat for a few months and we hired a guy to come and solder (or whatever) the lines back together and recharge with R-22 freon. I was already told by 2 other guys that I would need a dryer. This guy has been doing it 20 years but this was a side job on a weekend. Is it possible that he just didn’t have access to a drier and wanted to make the money so he took the chance? Now he is trying to sell me a new outside central a/c unit! After about a month a wire came loose that goes to the blower fan in house and I was home and realized that the outdoor unit was running with no fan pushing it. There was frost all over the A-coil and I waited until it was melted and turned the air on and it worked fine for a week. THEN, I notice that it is not working well at all! It is not freezing up or nothing, just not pushing cold air all the time. And if I stand outside and listen to the unit, it sounds fine but every once in a while (frequent especially hottest part of day) it hisses and while doing this the outdoor fan sounds as if it is lacking juice and "bogs" out for a few seconds and then quits. After it started doing this, I went ahead and left it running today which was really hot and muggy out and when I walked in the house there was a very substantial temp difference! The thermostat read 79 like it usually does when it is that hot. By the way the thermostat is old and takes batteries, I have replaced them and pushed the reset button on it. It never has been very good. Could the thermostat be possibly telling that compressor to turn off and on real quick as in like a short or something? Also, just because the fan outside is running, is the compressor supposed to be running or does the compressor go off first (as in when it is working properly) and shortly after the fan (outside fan)? I am thinking this is more of an electrical issue, well at least I am hoping anyway.! By the way, it HAS NOT froze up ever except the time that the wire broke off the screw that was keeping the blower from blowing and allowing the outside unit to continue to run. And like I said, it ran for a week after all that happened and it was fine. What are the signs that the freon has been leaking out slow where the guy "soldered" the lines together? Thank you in advance for any help, we are miserable and also pretty broke!

Hi. I gather that the temperature is measured in degrees Kelvin for these matters, with 273 K being 0 degrees C. So that a temp in degrees Celsius plus 273 = that temperature on kelvin’s scale.

Also, It seems that the ideal gas law rules the relationships between the temperature, pressure and volume of any gas or any mix of gases as long as no phase change occurs, as in condensation of one or more constituents, and as long as no chemistry takes place. Nothing burns for instance. OK, I think I get all that.

But if that much is true why doesn’t "shop air" from any air compressor condense to a liquid as it comes out? As the gas (air) is squeezed to ten times atmospheric pressure its temperature shoots up to ten times hotter. That’s *2460* degrees Celsius if the air starts at 0 Celsius. That’s actually 273K raising to 2730K, but whatever. OK?

Of course heat flows from higher temperatures to lower and so the air compressor gets hot without the air within ever getting anywhere near 2460 C. And the compressor has a heck of a lot more mass than the air being compressed, so that it doesn’t get anywhere near 2460C either. And even then "specific heat" is more complicated than just a difference in density. Well OK. Not an issue here, or is it?

Here is the part I just can’t fathom at all; If the compressed air is at room temp, say 0 C, and it’s allowed to go from 150psi down to the 15psi of the atmosphere, then what keeps the expanding air from just liquefying?

The Ideal Law seems to predict that the room temperature (0C or 273K) air at 150psi should drop to 1/10th that temp at 1/10 the pressure. That would make it 27.3 degrees Kelvin, and that’s almost cold enough to liquefy hydrogen. Now I’ve never seen anyone hook an expansion (rocket) nozzle onto an air line but even without one it seems like at least the CO2 should condense out.

I’m pretty sure my reasoning and/or information must be flawed but I can’t figure out where the train jumps the rails. Can anybody please point out the obvious to me or should I just make a nozzle and see what happens? Is that how they make dry ice?

Anyway, Thanks.

I have a request by your advice. Last week, when I came back from an activity, I started my car and noticed the air conditioning system was not blowing cool air. Today I took it to a local Nissan dealer with the hopes the problem might be minimal and that I would get off with adding Freon, etc. No such luck. Here was the diagnosis (for which I had to pay 0):

"Customer states that the A/C is blowing warm air. Verified complaint. Found the A/C system empty. Tested and found the biggest leak in the evaporator. Also recommend the rec/drier and Schrader valves as well. Advise. Low pressure remained at 60 psi with the high at 170 psi. Recommend replacing the compressor also. 50 estimated cost.

Also needs power steering system power flush. 8 estimated cost."

So! My question to you is, can I get this done properly at a less expensive place?

Thanks,

William
It is a 1995 Maxima with only 42000 miles.

I changed the ac compressor on my 95 Honda Passport. 134a. I’m using the arctic air freon but I cant get it to blow cold. I let the air out of the ac system careful to not let the foamy stuff out. Let the gas out really slow so the solid dont come out. Then I refill it with the good stuff but it just dosent blow very cold. Should I be careful about "not" letting the foamy stuff out? The clutch went out is why I changed the compressor. It was blowing really cold then.

Apologies that this has been asked before (need & would much appreciate more detail).

The "Best Answer" was that apparently filling a sandblaster with water works wonderfully.

Has anybody else done this?

Do you know What specs of of air compressor you need? Mine is 2HP/150psi 2.6SCFM @ 90 psi, 6 gallon. If powerful enough, what sandblaster would you recommend?

(A website that confirms compatibility would be super). I have searched the web without luck.

Thank you!
Thanks Las Vegas: solved in way under 4 hours. Two different animals was my gut feeling but had wishful thing after seeing that post. (Won’t shop at Wal-Mart, but nice to know they can be had at a reasonable price). Thanks again!

I do normal body work out of my 2 car garage. I use tools such as a 6" D/A Sander, Inline Board Sander, 1/2" Drive Impact Wrench, Sand Blaster, DeVilbiss HVLP Spray Gun, and a Media Spot Blaster. I currently have a Campbell Hausfeild 60 Gallon Compressor, and have terrible problems with water in my lines. I have a water trap that does absolutely nothing. I am now getting a spare 10 gallon tank for the air/water to travel to first, then am going to get either one of those Toilet Paper water filters, or am looking at a DeVilbiss Desiccant Filter/Compressed Air Dryer. Any opinions on which would work best? The TP Filter is about 80 bucks, and the air dryer will be about 250. Which is better or are there any first hand users?
I will be moving my 2nd tank away from the compressor/tank when I get one. Along with the filter or dryer. I just need to know which one to get.
And I currently drain the water from the main tank about every 30 minutes of use.

I just bought a Campbell Hausfeld "pancake" 1 gallon air compressor and it states to turn the regulator but there is no regulator. When I let it run to fill up, the PSI gauge doesn’t move. What am I doing wrong? How long does it normally take to fill up a new air compressor? Do I let it run with or without the hose attached? The manual for a new user is really short and not helpful.
I just bought a Campbell Hausfeld "pancake" 1 gallon air compressor and it states to turn the regulator but there is no regulator. When I let it run to fill up, the PSI gauge doesn’t move. What am I doing wrong? How long does it normally take to fill up a new air compressor? Do I let it run with or without the hose attached? The manual for a new user is really short and not helpful. Here is what I bought: http://www.walmart.com/catalog/allReviews.do?product_id=9189093
The diagram shows only power switch, safety valve, drain valve, and PSI gauge.