2nd Gen Non-Engine/Transmission Help HOT A/C at idle

[pholt]

I have a 2001 2500 4x4 and my A/C will freeze ice on the highway but at a idle it warms WAY Up. I bought a A/C gauge today and the low side is about 46lbs so that should be fine right? Either the more revs the motor is turning the better it cools, or it is the air moving over the condensor?



is there not enough air moving over the condensor? this is absolutly not going to work here in Oklahoma, what can I do? should I put a flexlite fan in front of the radiator, or is there another problem??



I bought a diesel just to avoid this problem, I hate hot running cars and I want my truck to be able to idle 10 to 20 minutes at a time and stay COLD.



Now this is in 90+ degree temps, in the 80's it was OK.



Thanks in advance.



Paul Holt

 

[B.G. Smith]

At 90 deg. outside temp and the engine running at 1,000 rpm, the suction pressure should be 50 to 60 pounds and the air coming out the center outlet discharge should be 60 to 70 deg. F. You should also run the ac in the recirculate mode when in stop and go traffic. Is the clutch cycling a lot when you are at idle? If so, you may be slightly low on refrigerant. Other problems could be the blend air door which I believe has an electric actuator. If you had restricted air flow at the condenser, the pressure would be higher. If you add 134 to the system, do it slowly and not over a half can at a time and see if it improves. Too much refrigerant is not good either. bg

 

[Forrest Nearing]

like he said, 46 is a little low at idle for 134... I run mine at about 55 at idle. I'm in Dallas, so AC is very important to me. we haven't gotten REALLY hot yet, but my truck cools VERY well... driving around it gets so cold that it hurts after a while and I gotta turn it down.



obviously it'll cool better/quicker w/ air moving over the condenser, but I don't notice any adverse cooling from being parked.



recently I replaced all the seals and hoses because I developed a leak somewhere. I drew vacuum on it and charged it up, and it's icy cold now.



I'm gonna have to make a new hose and recharge it again when the twins go on! LOL!



Forrest

 

[pholt]

I have it running now it is about 91 outside and it is showing about 54 on the low so far I have not seen the clutch cycle at all, it has been running about 5 minutes, I am going to get a temp gauge to see what temp it is blowing, but at idle it is not cold enought, now running down the road it is great. Should i add freon?

 

[pholt]

Ok went and got a thermometer and it is blowing about 70 at a idle and when it is 100 that wont do it, should I add freon, the low side is reading about 54 at a idle. Now like I said going down the road it will run you out of the truck it is so cold, but around town it just aint doing it. the truck is still running out there freon ready if you guys say go, what should I do?

 

[pholt]

ok just went back outside it is up to blowing 80 now and the a/c clutch did cycle off and on. but 80 thats no good.

 

[Forrest Nearing]

you MIGHT be dealing with a little leakage... I'd top it off to about 60psi on the low side and see how it goes...



Forrest

 

[Forrest Nearing]

oh yeah, I added a new orifice tube when I serviced my AC. just FYI

 

[pholt]

ok going to 60 be back in a few.

 

[pholt]

ok, this is taking forever, the thing has sucked down about half the can and the pressure has not gone up. I have unhooked and restarted. So I guess it is low. But this is going to take a week for it so suck in the freon. Is it this slow?

 

[B.G. Smith]

You can run the rpms up a little to lower the suction pressure and shake the refrigerant can and hold it near something warm on the engine. bg

 

[pholt]

ok, this is weird. this thing has finally sucked down about 3/4 can after 20 minutes and the the low pressure is now reading lower than it was before, but it is cooling better, I am going to keep adding freon until It gets colder or hits 60 either one. Can I speed up this process any, I have a cheap interdynamics gauge and filler and it is taking forever to take the freon.

 

[B.G. Smith]

Hey man, it's 8:00pm, it,s gotta be cooling off some outside, even in Tulsa, that and the fact that it is cooler inside the truck will account for the lower pressure. You need to try to find a buddy with an electronic leak detector tomorrow and see if you can locat where you are losing the charge. Look good at all teh hoses and where thy are connected to the condenser, ets, the "o" ring connectoions are prone to leak. You hear lots of folks talk about putting dye and stop leak in the system but I was tought that the only thing that should be added to a refrigerant systm was oil and refrigerant. I won't say have fun, since it sounds like you already are. By the way I used to live in Checotah and bought my truck in Bartlesville. bg

 

[pholt]

Actually B. G, it is still as hot as HADES here, still pushing 90+ my family is back in the pool and I am in the driveway with my noisly ass diesel running for a hour, it took a can and the temp inside went from 80 to 70 it is getting better onto the second can. Yea I need to find the leak, but if it is not bad I will leave it alone, since 134 is so cheap.

 

[B.G. Smith]

If I were you I would stop where you are now and see how it performs tomorrow in service. I think the whole system only holds about 28 ounces. bg

 

[pholt]

It only holds 2lbs? I thought it would be much more than that. I will stop and see what it does, it did cool off about 10 deg's but I think it needs to be blowing 60 not 70. I shut it off and let it cool down and I will check the pressure again and see how it works.

 

[Forrest Nearing]

you can speed it up by inverting the can and holding the engine at 2,000rpm



Forrest

 

[tp0d]

I bet you have a condensor leak under the dash. Unfortunately the dodge condensors seem to have a lot of faults, my dad's went at about 80k, luckily it was covered by the dealer... We used an electronic 134a detector, florescent dye, etc,etc, and could not find the leak. finally took it to the dealer, they changed out the condensor without a question, and its been like ice now, truck has about 117k... ohya, in the testing time when he was adding can after can into the truck, I was getting headaches and stuff while riding in the AC... the AC would work, but only for a day or two before going hot. I dont believe the talk about 134a being non-toxic... thats bs



hope you're still in warranty...





good luck



-j