A/C vent air temp question
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A/C vent air temp question
I was wondering if anyone out there can post up their center vent temps, ambient temp, and what refrigerant they are using?
Im curious as to what is possible (also what I can expect) with different refrigerants in my car.
I know its probably a long shot, but figured I'd atleast ask lol
Im curious as to what is possible (also what I can expect) with different refrigerants in my car.
I know its probably a long shot, but figured I'd atleast ask lol
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Re: A/C vent air temp question
if temp outside is 90 or less you should get a vent temp of 40deg. 100 outside vent temp of 45/50. but it also depends on the humidity and if you system is in proper working order.
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Re: A/C vent air temp question
Center vent 37, vent gets frost on it set to max, outside temp 95-100 and still use R12. Just had my system gone through earlier this year.
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Re: A/C vent air temp question
I just checked my temp at the center vent at 35°. I was idling in the driveway on a 72° day though. Oh, I'm running 100% freeze 12.
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Re: A/C vent air temp question
Thanks for the replies.... If I can gather all the things needed this weekend I'm going to fix my A/C! I'll post up vent temps afterwards
After reading Reid Fleming's review about autofrost, Im going to give it a shot. *crosses fingers*
After reading Reid Fleming's review about autofrost, Im going to give it a shot. *crosses fingers*
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Re: A/C vent air temp question
MAX A/C, Slider all the way towards cold:
Slowest fan speed: 29°F (rare...more likely 30)
2nd fan speed (most common setting): 31°F
3rd fan speed: aprox 33-34°F
Never bothered to measure on fastest fan speed.
Switching from MAX to NORM, the 31° number above becomes 41°.
I run R406a as a refrigerant. The above are with the stock low psi cut off (26 psi in my car). I suppose it's possible to maybe suck an extra degree out of it, but I doubt it. The 29 number was very brief. Basically low 30's is what I can get. The car cools down very quickly as well. Even on the muggiest of Houston days, I can get the in-cabin humidity down into the mid 30% range within one block. From there the temperature inside starts coming down.
I have the same GTA as you (black). Also have black leather. I need all the help I can get. One of these days I'm gonna tint the back window.
At 80°/70% outdoor conditions (Houston), I measured 70°, 29% humidity inside. At 95° and low humidity (Vancouver), I've seen it still blow 31° out the ducts driving around town. In Houston in the same 95° weather but with much higher humidity (60%), it tends to blow around 33°, although 31° is possible on the highway.
Slowest fan speed: 29°F (rare...more likely 30)
2nd fan speed (most common setting): 31°F
3rd fan speed: aprox 33-34°F
Never bothered to measure on fastest fan speed.
Switching from MAX to NORM, the 31° number above becomes 41°.
I run R406a as a refrigerant. The above are with the stock low psi cut off (26 psi in my car). I suppose it's possible to maybe suck an extra degree out of it, but I doubt it. The 29 number was very brief. Basically low 30's is what I can get. The car cools down very quickly as well. Even on the muggiest of Houston days, I can get the in-cabin humidity down into the mid 30% range within one block. From there the temperature inside starts coming down.
I have the same GTA as you (black). Also have black leather. I need all the help I can get. One of these days I'm gonna tint the back window.
At 80°/70% outdoor conditions (Houston), I measured 70°, 29% humidity inside. At 95° and low humidity (Vancouver), I've seen it still blow 31° out the ducts driving around town. In Houston in the same 95° weather but with much higher humidity (60%), it tends to blow around 33°, although 31° is possible on the highway.
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Re: A/C vent air temp question
I'm one of those people who thinks A/C shouldn't be cool. It should be COLD. The colder it is, the better it will dehumidify.
At that 80°/70% figure, that's an outdoor dew point of 69° (and Houston gets up to 80° dew points during the peak of summer. Those days are brutal)....The 70°/29% is a dew point of 36°. The same dew point as Arizona when it's 115° and 7% humidity.
Needless to say, it feels a lot drier and comfier inside. I wish my home dehumidified this well.
At that 80°/70% figure, that's an outdoor dew point of 69° (and Houston gets up to 80° dew points during the peak of summer. Those days are brutal)....The 70°/29% is a dew point of 36°. The same dew point as Arizona when it's 115° and 7% humidity.
Needless to say, it feels a lot drier and comfier inside. I wish my home dehumidified this well.
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Re: A/C vent air temp question
Last year I paid a GM stealership to do the 134 conversion and it leaked out 2 weeks later. Not only that but while it did work the Tech could only get it down to *52 at the vent during idle. It sucked. I decided the go ahead and do it myself this year and picked up a new compressor, O-tube, and drier. I have the autofrost sitting here waiting along with the mineral oil for the flush to arrive so i can get all the old crap out and start fresh.
Well I didnt get my flush yet so I cant do anything Hopefully today.
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Re: A/C vent air temp question
As long as we are talking about air, what`s up when the compressor runs all the time even when the control is in the off position? It keeps the car plenty cool but I would like to turn it off sometimes.
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#13
Re: A/C vent air temp question
could be a short. there's a plug on the back of the silver can (think drier is technical term) that if shorted out engages constantly. I know this because I had to short mine out to get it to accept my refrigerant.
Oh and my story is that I paid $350 for tireman to redo it. half a year later it didn't work when I finally got to taking my car out.. They didn't tighten that giant locking bolt/tube on the back of the drier. Oh yeah, $40 worth of refrigerant had me pleased.
Oh and my story is that I paid $350 for tireman to redo it. half a year later it didn't work when I finally got to taking my car out.. They didn't tighten that giant locking bolt/tube on the back of the drier. Oh yeah, $40 worth of refrigerant had me pleased.
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Re: A/C vent air temp question
Even if clutch cycling switch on the accumulator/drier shorts out (unlikely), it would not keep the compressor on when the ac switch is off.
Unplug the compressor coil. It's the 2 wire plug at 12:00 o'clock on the compressor. Start the engine. If the compressor still runs, the clutch has seized. If not, the problem is electrical.
Unplug the compressor coil. It's the 2 wire plug at 12:00 o'clock on the compressor. Start the engine. If the compressor still runs, the clutch has seized. If not, the problem is electrical.
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Re: A/C vent air temp question
ringo234,asting &black89ws6, thanks fort the ideas to look at. Titan, thanks for your input, I did`nt think it should either. The compressor runs anytime the ignition is in the "run" position. I will check out your ideas and let you know when I find out what is going on. Thanks again, Jim
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Re: A/C vent air temp question
Finally finished this....
Was getting 41* out of the center vent on "max" with the second lowest fan speed. It cools pretty good.
*crosses fingers* I hope it doesn't leak out
Was getting 41* out of the center vent on "max" with the second lowest fan speed. It cools pretty good.
*crosses fingers* I hope it doesn't leak out
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Re: A/C vent air temp question
41 is a heck of a lot better than 52 degrees. Was the the 41 sitting at idle in the driveway or out on the road? If it's in the driveway, you should be able to get into the 30's out on the road. 30's is where it's at.
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Re: A/C vent air temp question
the a/c system prevents itself from going below a specific temperature which is usually right about 40. this prevents the the evaporator from icing up.
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Re: A/C vent air temp question
I always disliked that, the properly functioning a/c system should slightly frost the evaporator then cycle off. I adjust all my cycling switches down to 24 PSI on R134a. That gives me 28*F at the evaporator. When the evaporator starts to lightly frost the slight reduction in heat entering it causes the pressure to drop further and cycle the compressor off which thaws it. My air is blows ICY.
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Re: A/C vent air temp question
41* was in stop and go, it got to about 38* on the highway yesterday and was getting about 45* at idle (still). I'm pleased with the performance thus far.
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Re: A/C vent air temp question
I always disliked that, the properly functioning a/c system should slightly frost the evaporator then cycle off. I adjust all my cycling switches down to 24 PSI on R134a. That gives me 28*F at the evaporator. When the evaporator starts to lightly frost the slight reduction in heat entering it causes the pressure to drop further and cycle the compressor off which thaws it. My air is blows ICY.
The early high performance test version of Autofrost was called GHG-HP. It had 65% R-22 instead of Autofrost's 55% R-22 content. It was good for 23-25°F duct temps. A cycling compressor was mandatory or else you needed to put in a defrost timer if you had a variable displacement compressor. People didn't like it. They said it was too cold and that the regular version of Autofrost (R406a) was good enough. That stuff has been out of production for almost 20 years now. Illegal to install. Impossible to get.
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Re: A/C vent air temp question
I always disliked that, the properly functioning a/c system should slightly frost the evaporator then cycle off. I adjust all my cycling switches down to 24 PSI on R134a. That gives me 28*F at the evaporator. When the evaporator starts to lightly frost the slight reduction in heat entering it causes the pressure to drop further and cycle the compressor off which thaws it. My air is blows ICY.
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Re: A/C vent air temp question
The low pressure cycling switch is adjustable by the screw in the center, between the terminals. Remove the connector and you will see what I am talking about. I want to say that 1/8 turn gives about a 2 psi difference. Lets say you rev the engine up to 2,000 rpm and the pressure switch cycles the compressor out at 30 psi (R12 pressure switch) and you want it to be 24 psi. You would turn the screw counter clockwise 3/8 of a turn. I retrofitted my 1997 Chevrolet Express with the non-adjustable accumulator mounted cycling switch to an adjustable R134a cycling switch (95 G20 Van). I was able to adjust the cycling pressure from 30 psi down to 22 psi. That brought the vent temps on high/recirculate in 100* weather from 55* down to 45* by keeping the compressor on longer, getting the evaporator colder, and taking more moisture out. That improvement is HUGE.
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