SPONSORED LINKS

A/C is not cold when idle

Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 2011 KIA CADENZA
  • 3.5L
  • V6
  • 2WD
  • AUTOMATIC
  • 60,000 MILES
Hey guys whats up, I have noticed my car's A/C is not getting cold when it is idling and it make a little hissing noise.
I have taken it to a repair and have checked the level of gas and he said the gas level is fine. He said it is due to a compressor.
So I am not sure if it is true or not.
SPONSORED LINKS
Friday, September 28th, 2018 AT 4:19 AM

80 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning.

If the unit works when off idle going down the road, it sounds like the compressor is working.

As far as at idle, is the cooling fan working pulling air through the radiator?

Are the fins of the radiator and the AC condenser free of all dirt and debris? Common problem for this issue.

Do you have gauges to test the high and low side pressures at idle?

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 5:43 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
I checked for the debris and dirt and it is free and the condenser fan is working when the A/C is on.
The mechanic guy only checked the low pressure and he said the level is good. Is it important to check the high one as well? And if it is on what level it should be? I do not have the gauge but if if can get so I can check.
But he said your compressor qualification is not good. So I am not if it is true or not. He said the compressor need to be replaced, but I do not think this issue is due to compressor.

Notes:
Sometime when the weather is not that hot it is cooler than hotter weather.
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 8:01 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
You cannot tell Freon level from pressure.

Yes, you must check the high side as well. Would love to know these pressures while it is idling.

You need a new shop that knows about AC. The shop you were at does not know how to check the AC system.

Roy
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 8:16 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
Oh okay, then how do I check the Freon level then?
Definitely I am going to look for another shop.
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 10:04 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
If you have a site glass on the dryer, you can tell if it is clear with the AC on.

Beyond that, you need to recover the Freon and measure it against what is supposed to be in the system. There should be a tag under the hood as to the amount of Freon required in the system.

Roy
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 10:09 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
So you mean this issue is not related to compressor right? Just want to make sure because I do not want to get fraud by the mechanic.
What do you mean by site glass on the dryer?
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 11:22 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Once I know the pressures I can answer about the compressor. At this point I doubt it is.

On the receiver dryer there may or may not be a sight glass to see the Freon. It will be on top of the dryer.

Roy
Was this
answer
helpful?
Yes
No
Friday, September 28th, 2018 AT 11:58 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
Okay, I took it to another mechanic and looks like the high pressure pipe has oil all over it especially from the bottom near to compressor. And he said the pipe need to be replaced as well as the compressor. I attached the picture aa shown below the leak part marked with arrow.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:11 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
The line looks like it is leaking but why did he tell you the compressor?

It could very well be low in Freon from the leak.

Roy
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:15 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
I told him why I need to replace the compressor if the leaking is from pipe he said it was due the compressor fault. But I did not believe him I think he was trying to rip me off.
And he checked the low pressure from Freon he said it is okay.
So but most likely the leak is near to compressor end to high pressure pipe.
So I am not sure what to do.
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:25 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Compressors do not cause a leak from a line. It is the line that has worn out.

Looking at low pressure is not an indication for Freon level.

Roy
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:27 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
So, I only need to repair the high pipe the end of the pipe that goes to compressor it has all cover like an oil.
I told him to check the high pressure as well using a gauge he said it does not need only low pressure needed for measuring Freon in a low pressure and he said its around 55-60 psi and there is no problem with Freon level.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:34 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
He is wrong with not checking the high side. The low side is too high. It should only be 25-35 lbs. 50-55 lbs is too high. That indicates either a bad expansion valve or too much Freon.

Roy
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:40 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
But what about the hissing sound when AC is on? Is that due to that leak as well? I can hear it from inside and outside.
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:41 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
It could be but I am not there to hear it so anything I would say would be a guess.

Roy
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:45 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
I could wrong ng about the 50psi because it has other unite so it maybe another unite like a metric system I did not see it very clear I may go for another mechanic.
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:45 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
I just want to make sure that hissing sound is not from the compressor. The sound is exactly like this one in this video.
https://youtu.be/kbjmouPllSs
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 7:49 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
That is the sound of Freon flow. It may be low in Freon from the leak.

Roy
Was this
answer
helpful?
Yes
No
+1
Saturday, September 29th, 2018 AT 7:54 AM
Tiny
BAKHTIAR DUSKY
  • MEMBER
  • 96 POSTS
It is exactly what did you said. I took it to another mechanic he said Freon is less than a half because of the leak and yea he said the hissing sound is from compressor because there is not enough Freon to push that is why it makes that noise hissing sound, but there is nothing wrong about compressor but he is going to check anyway he is going to repair it after tomorrow then I am going to post the results.
It is going to cost me about $80.00.
Pipe = 25$
Freon=40$
Labor =8$
Thank you for your time. I learned a lot from you.
Was this
answer
helpful?
Yes
No
Saturday, September 29th, 2018 AT 8:50 AM
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
You are welcome.
Roy
Was this
answer
helpful?
Yes
No
+2
Saturday, September 29th, 2018 AT 3:35 PM

Please login or register to post a reply.

Related Air Conditioner Not Working Content

Fix an Air Conditioning Not Working Video
VIDEO
Fix an Air Conditioning Not Working Video
Instructional repair video
Air Conditioner Not Working
GUIDE
Air Conditioner Not Working
Like any sub system in today's car a problem and be minor or a little more involved, this guide will help you find the problem and perform repairs. You can be the judge if...

Sponsored links