My a/c when it's on lowest setting (coldest) only blows semi cold air in the mornings but any other time it blows hot or ambient air. The system has already been evacuated and refilled with the proper amount of PAG oil and freon. Readings with an A/C guage are about 20-40psi on the low side and roughly 200-250 on the high side. Compressor is running properly. So not sure what it could be, does anyone have an idea of what the problem could be. The system also doesn't seem to have any leaks of any sort

 

How cold is the suction line? (the larger diameter one coming out of the evap at the firewall and on to the compressor)
Pressures sound good, (well...20 is a bit low, possibly indicative of evap icing) so if that line is nice and cold, I'd start looking at internal water-valve leaks for the problem. (if the water valve is opening or leaking internally, you are getting hot coolant in the heater core defeating the cold air produced by the evap.) Doesn't take much to overwhelm a properly operating A/C.

 

Not sure how to check the coldness of the line... just feel it while the a/c is running?

 

Yep.
It should have some moisture on it.. (dry ones are likely discharge or liquid line & should be uncomfortably hot.
Suction line should be about 35_45 dog F. Ie feel "cold" rather than "cool"

 

Went to try and pick up some parts today and ran the ac for about a 20 mile drive and check the low side line where I usually put freon in and the hose is pretty warm like there is nothing in the system. Yesterday when I refilled with freon I didn't hear any apparent leaks and it seemed to hold a pretty good vacuum after evacuating the freon out and leaving the gauges hooked up for 10-15 mins.

I was told it could be a bad heater valve as my heater doesn't work also when I turn the temp all the way up via the ac control panel. Could the two not working be related?

 

All things are possible, but I'm dubious of a connection between the two problems you describe. Perhaps there is some theoretically possible stuck-valve position that would allow enough hot-water to leak into the heater core to make your A/C lukewarm yet be so small as to not provide sufficient heating in winter....but that is stretching the imagination a bit...and it doesn't explain a hot a/c suction line.


For your heater woes, I suspect you have the all-too-common clogged heater core, or perhaps worn out brushes on your heater water pump (or both.) I thought my water valve was sticking closed, not allowing hot coolant into the heater core, when in fact, it only needed a good flush:
https://www.jaguarforums.com/forum/x...winter-102192/


As to your A/C problem - look around all your lines for an oil-trail. When refrigerant leaks, it carries the oil out with it. If you had high-side pressure in the 250 psi range and simultaneously low-side pressure around either side of 30, you were cooling something somewhere! Potentially, it could've leaked out since you had the gauges on it, resulting in today's performance?

 

I'm starting to lean towards either a clogged receiver dryer or a bad expansion valve.

I may just evacuate the whole system of freon again and check the receiver dryer to check if there's a problem I see in there. Is there anything in particular I should look for?

I assume if there's nothing wrong with the receiver dryer then it's more than likely a bad expansion valve which I'm hoping it's not because I've read that, that's a big job.