A/C High/low PSI - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

jbassking · 08-17-2018, 12:35 PM

I want to check the pressure of my A/C and was wondering what the high side and low side PSI should be.
I have a 2012 SS.

Thanks!

jbassking · 08-22-2018, 01:32 PM

The issue I'm getting is my compressor turning off at highway speed - ~70 MPH. As soon as I slow down, it turns back on.
I'm pretty sure I over charged the system but can't be certain since I don't know the actual PSI it should be.

JerTM · 08-22-2018, 01:39 PM

It changes with ambient temperature. What pressures are you reading, and at what ambient air temp?

silversleeper · 08-22-2018, 02:57 PM

Quote:

Originally Posted by jbassking

The issue I'm getting is my compressor turning off at highway speed - ~70 MPH. As soon as I slow down, it turns back on.
I'm pretty sure I over charged the system but can't be certain since I don't know the actual PSI it should be.

I had this exact issue with a different car. I kept trying without success to just guage and refill the low side.
I fixed it by getting a harbor freight gauge kit on sale where you can check the high AND low side pressures and added until it was near typical specs specified in youtube videos. I don't remember but high side mostly is what I was watching and think it was about 165psi but double check that number.
I bought a new filter and sensor but didn't need them it fixed it by getting the fill-pressure correct.

Spurshot · 08-25-2018, 07:28 AM

The system has low and high pressure switches to protect the system. If you over charge it, it can exceed pressures it was designed for and trip the high side switch to cut the clutch engagement. Similarly, if pressures are too low, it will not engage the clutch. Another danger of blind over-fillinig system with refridgerant is a liquid 'hydraulic' lock where the compressor gets damaged.

Our vehicles also are designed to cut the clutch engagement when we accelerate at high throttles.

It's important to stay within the pressures on the chart for the specific ambient temperature or the system may either not cool well or the evaporator or expansion valve could freeze up which limits the cabin cooling.

Spurshot · 08-25-2018, 12:56 PM

If you have an unknown quantity of charge in the system, probably best to evacuate the system again, recharge with a weighed amount.

jbassking · 08-25-2018, 01:04 PM

I'm going to get a gauge manifold and check out the pressures again.
I had used the chart that Spurshot posted with a gauge set and my pressure seems right but at ~2000 rpm it turns off. Once I slow down again, it comes back on.

Doesn't the pressure increase when the engine is running faster?

CamaroCracka · 06-27-2023, 05:57 AM

Is this what we can expect from AI?

redcoats1976 · 06-27-2023, 07:48 AM

leave Al out of this,who knows what hes been doing since they cancelled tool time.

el ess A · 06-27-2023, 08:09 AM

Quote:

Originally Posted by redcoats1976

leave Al out of this,who knows what hes been doing since they cancelled tool time.

He's been trying to get people to grab his pocket hose.

08-17-2018, 12:35 PM	#1
jbassking Drives: 2012 SS Join Date: Aug 2017 Location: Lake Worth, FL Posts: 99	A/C High/low PSI I want to check the pressure of my A/C and was wondering what the high side and low side PSI should be. I have a 2012 SS. Thanks!

08-25-2018, 07:28 AM	#5
Spurshot Drives: 2014 2SS blue Join Date: Jun 2016 Location: Socal Posts: 689	The system has low and high pressure switches to protect the system. If you over charge it, it can exceed pressures it was designed for and trip the high side switch to cut the clutch engagement. Similarly, if pressures are too low, it will not engage the clutch. Another danger of blind over-fillinig system with refridgerant is a liquid 'hydraulic' lock where the compressor gets damaged. Our vehicles also are designed to cut the clutch engagement when we accelerate at high throttles. It's important to stay within the pressures on the chart for the specific ambient temperature or the system may either not cool well or the evaporator or expansion valve could freeze up which limits the cabin cooling. Attached Images __________________ Last edited by Spurshot; 08-25-2018 at 07:46 AM.

08-25-2018, 12:56 PM	#6
Spurshot Drives: 2014 2SS blue Join Date: Jun 2016 Location: Socal Posts: 689	If you have an unknown quantity of charge in the system, probably best to evacuate the system again, recharge with a weighed amount. __________________

06-27-2023, 05:57 AM	#8
CamaroCracka Drives: 2010 Turbo LS3 Join Date: Dec 2009 Location: Palm Bay, FL Posts: 2,736	Is this what we can expect from AI? __________________ 2010 SS - On3 kit with downpipe cutout, CTR 78/80, CompCam 239/251 620/632 122+4, E85, Z28 suspension and ZL1 diff with Outlaw axles. Gen6 ZL1/1LE brakes. 2011 Vert - 416/w 230/236 .612/.602 115lsa, 1LE suspension w/32mm rear bar. Z28 diff. ZL1 brakes.

08-22-2018, 01:32 PM	#2
jbassking Drives: 2012 SS Join Date: Aug 2017 Location: Lake Worth, FL Posts: 99	The issue I'm getting is my compressor turning off at highway speed - ~70 MPH. As soon as I slow down, it turns back on. I'm pretty sure I over charged the system but can't be certain since I don't know the actual PSI it should be.

08-22-2018, 01:39 PM	#3
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	It changes with ambient temperature. What pressures are you reading, and at what ambient air temp?

08-25-2018, 01:04 PM	#7
jbassking Drives: 2012 SS Join Date: Aug 2017 Location: Lake Worth, FL Posts: 99	I'm going to get a gauge manifold and check out the pressures again. I had used the chart that Spurshot posted with a gauge set and my pressure seems right but at ~2000 rpm it turns off. Once I slow down again, it comes back on. Doesn't the pressure increase when the engine is running faster?

06-27-2023, 07:48 AM	#9
redcoats1976 Drives: LT W/2LT,blue metallic Join Date: Jul 2016 Location: central florida Posts: 4,915	leave Al out of this,who knows what hes been doing since they cancelled tool time.