Correct AC pressures high/low?
Thread Starter
Launching!
Joined: Nov 2008
Posts: 286
Likes: 131
From: Knoxville, TN
Correct AC pressures high/low? Have been trying to find the correct high low pressures for ls1 camaro. I've seen some generic charts, but I also read it's better to find vehicle specific.
Today at 84 degrees ambient with 55% humidity my car's low was 35psi and high was 246psi. This was with the air on max setting fan blowing medium speed.
Can anyone help me find the normal psi chart for our cars? I've searched and read several different things, one said my low is too low and high is normal. The other said my low is normal and high side is too high???
My AC symptoms are the AC blows ice cold, never has an issue keeping the car cold, but my accumulator and AC lines freeze up.
Also checked and my AC compressor is running. Today when AC was on, the compressor never shut off. The clutch stayed spinning. Not sure if that's bc it was so hot or I've got another issue with possibly the cycling switch. Anyways, any help is appreciated!
Today at 84 degrees ambient with 55% humidity my car's low was 35psi and high was 246psi. This was with the air on max setting fan blowing medium speed.
Can anyone help me find the normal psi chart for our cars? I've searched and read several different things, one said my low is too low and high is normal. The other said my low is normal and high side is too high???
My AC symptoms are the AC blows ice cold, never has an issue keeping the car cold, but my accumulator and AC lines freeze up.
Also checked and my AC compressor is running. Today when AC was on, the compressor never shut off. The clutch stayed spinning. Not sure if that's bc it was so hot or I've got another issue with possibly the cycling switch. Anyways, any help is appreciated!
There may be vehicle specific pressure charts, but I’ve never seen one. All the charts I’ve seen show correct pressures at a give ambient temp for a specific refrigerant type. The system capacity will dictate how much refrigerant is needed to achieve the correct system pressure (at a given ambient temp). But unless you weighed the refrigerant as you were filling the system, it’s a moot point now.
The fact that your compressor is not cycling indicates your system is likely slightly under charged. It’s possible the high pressure cutoff switch failed but they typically “fail safe”
The fact that your compressor is not cycling indicates your system is likely slightly under charged. It’s possible the high pressure cutoff switch failed but they typically “fail safe”
TECH Fanatic
Joined: Dec 2017
Posts: 1,467
Likes: 265
From: Bossier City, Louisiana
Yes, I think slightly undercharged. The 35 PSI low side number and that you are seeing icing is the tip off. I'd start adding refrigerant a little at a time while watching the gauges.
1 - Purge the air out of the input hose first.
2 - Don't turn the refrigerant can upside down. This allows liquid refrigerant into the system and liquids are not compressible. Damage to the compressor can occur. A little heat gun heat or a little torch heat can speed this up with the can upright but use caution with the torch.
Rick
1 - Purge the air out of the input hose first.
2 - Don't turn the refrigerant can upside down. This allows liquid refrigerant into the system and liquids are not compressible. Damage to the compressor can occur. A little heat gun heat or a little torch heat can speed this up with the can upright but use caution with the torch.
Rick
