Help....advanced A.C. problem!!!

[asp84]

I Have a 1991 Explorer with a 5.0L V8 Installed.
The 1992 5.0L V8 has a 1994 Mustang 5.0 Short Front ACC kit.
The Air COnditioner is also a 1994 stang R-134 cmpr.
The AC tubing is all from a 1995 Cobra 5.0 R-134 unit
The Heater/AC box on my Firewall is from a 1994 Ford Explorer that had an R-134 unit.
The little Black canister attached to my heater/AC box (the receiver/ dryer......whatever you call it) is also from a 1994 Explorer w/ R-134A
The Air COnditioner cooler behind my grill is from my 1991 Explorer R-12 system.

So As you can see, my Air Conditioning system is a mismatch of different ford vehicles. But the Good thing is all the garter spring clips snapped together like they were meant to be there. The Air Conditioning also blows cold. ( when I lived in Washington that is)

Now the problem. I Now live in Phoenix, Arizona area which can get a little hot if ya know what I mean. My Air Conditiong works, but on days when it is really hot outside, ie over 100 degrees, my AC, barely blows cold. As soon as nightime sets, and it gets to 80-90 degrees, The AC blows a little bit colder, but still not freezing like it should. I have an extra bottle of R-134A handy, but it doesn't want to seem to take anymore. (even with the engine and AC on)

My Question is: All of the Air COnditioning components had been exposed to the atmosphere for a good 5-6 months before they were hooked back up again. Can any of these components become contanminated? (especially the little black canister attached to the Heater/AC box that has the low side input and cycling switch on the top of it? or the orfice tube?????

Now, does anybody want to take a stab at this? Remember, were dealing with Ford Explorer and Mustang parts which are very similar.

Thanks in advance!
Al

[asp84]

my main question really is; can AC parts can be ruined by being exposed to the AIR for a long period of time. If it is possible, I will replace that part, and get the system flushed. By the way, my engine has a 180 degree thermostat, and the engine temp with the AC on, on a 105 degree Phoenix day in traffic runs at about 190 degrees. (I have a Mechincal Fan)

[JDraper]

Exposing them to air won't ruin them, but you may have contaminants in the system. You might want to consider a complete purge and refill. Another thing with R-134, if you put too much in, it will act just like there is too little, i.e. not enough cool air. Also, with the mismatched system, you might not have a big enough condenser for the system volume.

Just a couple of thoughts....

[97emerald]

The black cannister,(accumulator) has a dessicant material in it which is supposed to absorb moisture. If this was exposed to air and humidity for extended period of time, I would definitely replace this part as well as have the system flushed and evacuated and recharged. The r12 condensor could also be a factor. R134 systems typically have larger condensors. If your high pressure readings are normal, then the condensor should be sufficient.

[taxx]

I am sure what was said above is correct. It is recomended and required for warrenties of new parts, that anytime you replace ANYTHING in your a/c system or open it up you must replace the accumulator. But too you may need a larger compressor. 134 doesn't get as cool as good old 12, but they do sell additives that are supposed to make it cooler.

You may want to go to an A/C shop for a flush and fill like said before and see what they say about the compressor and accumulator. But go somewhere that specializes so they actually know what they are saying.

[dogfriend]

Long ago, I used to work for a Class 8 truck manufacturer...

I recall that whenever the system was opened up for any reason they recommended that the receiver/dryer (also referred to as an accumulator above) be replaced. One function of the receiver/drier is to remove excess moisture from the system. When you expose it to the atmosphere, it will absorb moisture from the air and thus deplete its ability to remove moisture from the system.

Also, R-134a is not as efficient as a working fluid as was R-12. (It does not transfer heat as well). Because of this, you won't get the same performance out of the system unless you make the components of the system more efficient to compensate. From your description of the components, the one component that is not typically used in a R-134a system is the heat exchanger mounted in the grill (also known as the condensor). You might want to replace this one with a larger unit to get better performance.

[asp84]

Thanks for all the help guys.

I think my system is highly contaminated. I will replace the orfice tube filter and the (Receiver).

Any ideas on the (receiver/dryer/ accumulator) cost?
Thanks,
Al

[Rick]

Welcome to AZ! So when are we going to get together

[asp84]

Rick,
I was just over by your house near Sun City and Glendale today. (showing somebody my v8 conv.)

let me know.

asp84@earthlink.net

Al

[Rick]

Let's do lunch or dinner sometime. We're available just about any time. 602-896-8813.