Model: Grand Cherokee
Engine Size: 3.7
Refrigerant Type: r134a
Ambient Temp: 85
Pressure Low: 45
Pressure High: 500
The compressor was cycling on for 30 seconds until it got up to 500PSI then shutting down for 30 seconds and starting all over again. Static pressure is 95Low 100 High.
Where should I start?
Pressure that high is usually caused by an (1) internal restriction, (2) no fan or restricted air flow to remove heat, or (3) too much refrigerant.
What has been recently done?
This AC system has never been touched. All original. When I turn the AC on, the electric fan(the only fan on the vehicle) does not come on. Should the fan be running at all times when the AC is on? The pressure slowly increases from Static 100 All the way to 500 when the compressor shuts down. Should the fan run when the compressor is running? ALso it takes 30 minutes after the compressor has last run for the high and low side to reach 95 and 100. Not sure if that is important
Edited: Thu July 03, 2014 at 10:06 PM by themow
That is the problem, the fan needs to come on long before the high side gets to 500. Some vehicles are set up so the fan doesn't start immediately, but it is tied to a pressure sensor which will start it around 250 psi.
fan is bad. New one ordered
Problem fixed. Fan was the issue. Thanks for the help
We've updated our forums!
Click here to visit the new forum
Copyright © 2016 Arizona Mobile Air Inc.