04 A/C Issues, high pressure on the low side, vice versa

[SoundPer4mance]

Sorry for the repost, but I think this is the correct forum for this one

Hey guys, my wifes 2004 mountaineer (4.0) Front and rear AC has not really blown COLD air for a while. A buddy of mine pulled a vaccuum today and refilled it, but with the AC on max, front and rear, the low side pressure is reading about 115 psi, and the high side is reading about 105. My friend thinks I should change the compressor and drier as he has seen this before and that was the case.

Before I spend all that money I wanted to get some input from explorer owners, make sure its not something simple like the orifice tube. Admittedly I know very little about how the AC system functions so any advice is appreciated.

 

[ranger7ltr]

Are you sure those are the right pressures while the system is running?

Because if it is, you definitely have some issues with this system....

First, what was the ambient temp when these pressures were measured?

Second, are there any obvious leaks in this system?

Third, the orifice tube could have been checked when the charge was removed before the vacuum was pulled..

But if the low side pressures are that high and the high side that low, I am surprised this system cooled at all...

I would pull that orifice tube,inspect the cooling fan and the condenser, and determine if the radiator needs cleaning and/or coolant replacement.

And if the pressures are actual and the gauges are not defective, this compressor is dying a slow[ or maybe quick] death and needs to be removed before it pukes the rest of its teflon seals and aluminum pistons into your condenser and a/c lines...
If the orifice tube shows any tar-like substances or solid particles you may have a "black death" issue...

 

[SoundPer4mance]

The pressures are correct, checked 2 different days with 2 different sets of gauges. Temp was about 75 or so last time we checked. Ill check the orifice tube and report back, thanks for the input

 

[ranger7ltr]

A couple of things to consider as well.. What is the vent temperature inside the truck with the system running?

Ideally the high side pressure should be 2.2-2.7x ambient temp so at 75F you should be seeing 170-210 psi and a properly working compressor and system would pull the low side to 20-40, depending on the heatload on the evaporator and system charge, etc...You may have a condenser issue as well here...

Probably a dumb question but was the system recharged by weight or by pressure monitoring the system gauges? And what level was your system vacuumed down? Here in Texas where I am I can pull a system down to 29-30 in hg. in about an hour or so but that may not be the case where you are...

Good luck on this and let us know what you find in the orifice tube...

 

[SoundPer4mance]

The vent temp was about 65F

If you guys can give me some tips on what to check, ill take it back to my buddies shop this week where he has the A/C machine. Let me know what you need to know and I'll get it for you, thanks for the input so far

 

[ranger7ltr]

ouch....That vent temp is not good...

I can't see how you are cooling the inside of your truck at all...

I would pull the system down and look at the orifice tube...

Since the system is discharged, pull the compressor and the accumulator and drain any oil out of them...

Then depending on the orifice tube condition, flushing the system or replacing the compressor, accumulator and condenser will be next...

I would like to know what level of vacuum you can get the system down to before recharge...

And is this a dual air system?