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A/C full - No leaks - STILL blows warm???

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10K views 13 replies 8 participants last post by  gbhs72  
#1 ·
I recently charged my A/C. The compressor engages just fine now, but it still blows piss warm air. It has no leaks. Any suggestions?
 
#2 ·
The valve that controls the air blowing over the heater core has crapped out or the blend-door rod has broken/dislodged. Or you have a vacuum leak in the HVAC system so the door isn't getting pulled closed.
 
#3 ·
Can I fix this or should I go to an A/C shop? Also, when the A/C is on full blast and the clutch engages, the metal unit where I filled does not get cold either. The metal unit near the passenger firewall does not get cold or sweat at all.
 
#4 ·
Did you pull a good vacuum on the system before charging?

An overcharged, low charged, air or moisture in the system(from inadequate vacuum before charging) will all result in same...no cooling or poor cooling.
 
#5 ·
I'm no A/C expert and just replaced pretty much the entire system with the exception of the Condensor and Evaporator. When complete, I just took it to a shop to have them evac and charge the system for me. Although the system was working great, it was working too well. It was actually icing up the entire system after about 10-15 min. and then there was zero airflow into the car. What they found was that the little $20 switch in the receiver/drier that I decided not to replace was bad and causing the Compressor to not cycle on/off as it should. So a stupid little piece that I just moved over from my old drier should have also been replaced at the time....live n learn.

Best advice I could provide is take it to a shop and have them do a quick diiagnostic of the issue for you. It may cost you an hour of Shoptime but at least you'll know and they have the tools and equipment I dont to get it done properly. GL
 
#7 ·
I'm no A/C expert and just replaced pretty much the entire system with the exception of the Condensor and Evaporator. When complete, I just took it to a shop to have them evac and charge the system for me. Although the system was working great, it was working too well. It was actually icing up the entire system after about 10-15 min. and then there was zero airflow into the car. What they found was that the little $20 switch in the receiver/drier that I decided not to replace was bad and causing the Compressor to not cycle on/off as it should. So a stupid little piece that I just moved over from my old drier should have also been replaced at the time....live n learn.

Best advice I could provide is take it to a shop and have them do a quick diagnostic of the issue for you. It may cost you an hour of Shoptime but at least you'll know and they have the tools and equipment I dont to get it done properly. GL
if the low pressure switch is always closed with NO / low pressure then the compressor will fail .. probably why the old one died. this is like running an engine with NO oil...
 
#6 ·
Thanks everyone. The system was almost full before I charged it. I did not evacuate it before I charged it and I know I overcharged it a little. I will have an A/C shop evacuate the system and recharge it properly. I'll post updates.
 
#8 ·
so the ac was not cooling and the receiver dryer was not cold ... if so then the orifice tube maybe bad [plugged up].... or the compressor is not pumping ..

temp door operation >>>>>>>>>...... does the hot air come out in hot ? and cooler air in cold ??? if so the temp door is working
 
#9 ·
You say your compressor is engaging (spinning), so the system should do it's thing ... even poorly. Since you are not detecting any cooling anywhere in the system (tubes, etc), your compressor is either simply not working internally, you actually don't have any Freon in the system, or your orifice tube is missing (or not working properly) and you are not getting a pressure / vacuum differential in your system. Without a high to low pressure transition, you will not get Freon to absorb heat (cool). You didn't say you hooked up a manifold to check your pressures (high and low), so I'm going to assume (respectfully) that you do not have the experience to fix this, and suggest you take this in to a shop before you inadvertently trash something ($$) ... and smack yourself. :)
 
#11 ·
the compressor leaking oil is what I had 3 plus years ago. replaced compressor ,filter dryer,seals,flushed the system. including the condenser/evap etc..

I mixed some dye in with the oil and added it to all of the components .. then vacuumed the system no leaks then charged it up .. still working ... the one failure I had was the filter dryer seal that came with it was defective so it was leaking at the low pressure switch .. I did not have to replace the refrigerant and that was the only issue.

the dye did reveal the leak easy ......did not have any cooling issues it was small..
with all the years of use there was a gray slime when flushing the system....

some will buy new condenser rather than clean the component .. flush products /air compressor and the use of water pressure ,then air compressor to blow out the cond is what to do ..
orifice tube screen can get plugged up when the compressor starts breaking up..
 
#13 ·
If he didn't change the accumulator and orifice tube, you may have trouble again soon. Those should always be done when the compressor is changed and are both cheap.
 
#14 ·
Well now. That's cool that you got it up and running again. I'll be replacing the entire system on mine.

Mark: Snowman-33