My A/C is not working well.

At MAX A/C and steady state (engine hot, 90*F ambient), the compressor turns on for about 18 seconds and off for about 5-10 seconds. Cold freon flows to the evaporator when the compressor runs but I don't feel any cold freon flowing to the accumulator. When the compressor stops, no cold fluid flows to the evaporator and I effectively get no cool air in the cabin.

First, is this a normal compressor cycle? 20s on, 5s off?

If not, is this an indication of something simple like low refrigerant level? Is there an easy test? Somewhere else I can use to isolate the problem?

Does anyone have an A/C system schematic?

Thanks,
-B

 

That typically means you are low on freon. Throw a can in there and see if that takes care of the problem.

 

Thanks. I just went to Autozone and bought three cans. A stop leak. A UV leak detector. And the IDQ fill kit with gauge.

I followed the stupid directions on the kit. It said to get between 45 and 55 psi on the low side. When I started I was at 40 psi. After three cans ~45 oz, I ended at 40 psi.

The A/C is much colder now. And both the evaporator and accumulator lines are cool (before just the evaporator and only when the compressor kicked on). The compressor also stays on now. But I'm afraid I may have overcharged the system. Is there an easy way to tell?

Thanks,
-B

 

i'm sorry to say that using a/c stop leak will cause future high $$$ expenses. as most a/c shops will either refuse to work on the system or flush and or replace all components in the system.. as the stop leak will eventually cause compressor problems, valves sticking and small passages to plug....
glad you got your system working better...

 

For an accurate full refrigerant charge, the best way is to remove the charge from the system, pull a deep vacuum on the system and weigh in the charge.

 

your fine .... rember this system is HUGE .. from empty i had to put in 5big cans

 

check the sight glass. if there's no bubbles. you have enough in the system... if it stays running, you need the cooling...
raise the temp control and the compressor should kick off...
glad your in the cool now..

 

I've been to auto zone orielys and VIP and no one could explain how to properly get my AC to work. Short cycling is most likely due to low refrigerant. The steps I took to get it working again were as follows. Go get yourself a bottle or two of refrigerant one having the gauge on it. Turn the AC on in your vehicle full blast. Find the low side port and hook the bottle up to it. Now every time the AC clutch kicks on or starts rotating pull the trigger on the bottle. The only time you get a accurate reading is when the clutch is on. Get the psi to the green and your ac should be cold again. The AC clutch will still turn on and off but it'll take longer, this is normal. Hope this helps some people. If anyone has any questions please feel free to reply I will try to answer to the best of my knowledge.

 

Ah, heck... Just read the HVAC FAQs, link is in my signature. They've been there for years.

No need to blindly resurrect an old, dead thread on your first post.

 

Thanks for the info. I posted here because this is all I could find. Hopefully someone sees your post and goes there. Just thought I'd be helpful and post my own experience in case someone happens to see it. And it helps.