What Low / High Pressure for the AC? 1999

[Neuner]

Just charged our '99 for the 1st time and it seems to be cooling the same as before but not sure.

I put in the required amount of refrigerant but the Low side pressure was at 50 and the high was at 360m both of which seems high? I've searched but I can't find what it's suppose to be.

 

[medtro]

Post in thread '2000 AC Low and High Pressure PSI'

Jul 21, 2019

From the service manual

• Mike6158

 

[vipergrhd]

Just charged our '99 for the 1st time and it seems to be cooling the same as before but not sure.

I put in the required amount of refrigerant but the Low side pressure was at 50 and the high was at 360m both of which seems high? I've searched but I can't find what it's suppose to be.

Are these reading in PSI? Did you use cans or a machine to charge the system? Was the system completely empty?

 

[Brandon Ryder]

Did you vacuum the system? Air in the system can change the pressures and is no bueno.

 

[Neuner]

Correct in that the readings are in PSI and I used cans. System was evacuated prior. Yes, I vacuumed the system.

The gauges I used were a loaner so I'm not trusting the reading. I ordered my own Mastercool set and will take readings with it following the posted service manual guidelines.

The readings I have posted above just happened to be under the service manual guidelines as well but with the rpm at 1,500.

 

[Brandon Ryder]

Do you remember the ambient temperature? If it was 100 degrees that could be normal. If it was only 70 degrees, then its high.
Could be overcharged. Could be an issue with the condensor(poor air flow, or blocked fins, basically not cooling). Was the fan turning on? It should have been if it was at 300+ psi.
Here's a great video on sort of general A/C diagnosis. goes over diagnosing pressures. jump to about the 18:20 mark to see the part about high pressure causes.