'93 Park Avenue. A/C not cooling properly. Checked the pressues and the low side reading was 22-25 psi. while the high side was running between 200-210. It appears the high side is too high and the low side is too low. Thus, giving me a blockage at the orifice tube? Correct?

Thanks

Tough one.. I'm going for back up...cover me.

That sounds to be about right, but I have a question. Has the system ever been compromised? Like a new compressor or other parts? That is the most common way for an orifice tube to become blocked.

There are rare occasions were there is some manufacturing material that comes loose and causes blockage of the filter there, but usually that reason shows itself before this many years have gone by.

Not that I know of. The Large low pressure line does not get cold, BUT the smaller low pressure line going into the evaporator does sweat and get nicely cold. The small high pressure line gets hot as it should. Looks like a blockage, but I don't want to open the system if not necessary because that'* a whole lot more work.

There is a particulate trap in the lower of the two lines that enter the radiator core. Clogged?

Is the evaporator core clean? Does anyone else remember the method for checking to see if it'* blocking air flow affecting cooling.

Just by blowing compresser air thru it? Is there any other way? It does seem that the driver'* side air is colder than the passenger air. This is one of those dual type units.