Twisted636

iTrader: (3)

so it was pretty hot today so i was gonna use the ac iv not used since i bought the car last year and it was just blowing out hot air. so i go to advanced auto get a recharge kit and start to put it in. i plug it up and it shows its over full in the warning bar, so i let almost all of it out that was in there and put just what it needed back in. it didnt work feels like it got just a little cooler but not much change at all. any idea on what is wrong? the compressor looks like it is spinning when i turn the ac on. i drove around for a few hours but never felt a change.

blue98Z

iTrader: (29)

I'd get the system done at a shop and they'll be able to pin point the problem quickly. Sounds like the compressor's goin bad though.

RPM WS6

iTrader: (3)

Are you able to hear the compressor engage when you turn it on? (should make a audiable "click").

If the gage shows that freon pressure is where it should be, but it's still blowing hot air, then my guess is some sort of issue relating to the compressor or a bunch of debris blocking flow across the condenser.

TooLateVTEC

iTrader: (2)

What he said ^.

Turn the radio off with the car running and listen for the click when you turn the ac on.

After that try blowing out the condenser with compressed air and water from a hose. Youll be surprised how much **** comes outta there.

99345hp

could also be a blend door issue, if the compressor is working and the air is still hot.

With the AC on does the dryer get cold? if it does then you most likely have a blend door problem and not a compressor, charge, or condenser problem.

Dal1as

Check for the click of the compressor turning on and if the condensor gets cold first like has been stated and go from there.

One word of advice for everyone though. Use your AC for at least a couple minutes every month. Otherwise seals and such dry up and you start having AC problems.

NC98Z

iTrader: (1)

And what if it doesn't click when you turn it on?

99345hp

If your waiting for the condensor to get cold then you are going to be there for an awful long time waiting. Especially because when the ac is working properly the condensor will get hot, since it is on the high side of the ac system.

If the compressor isn't clicking on, then you could have a couple problems.

Low charge- check static pressures to see if the psi is over what the low pressure switch needs to see to turn on the compressor.

Low pressure switch problem- This switch is there to make sure there is enough charge in the ac to carry the oil the compressor needs to not burn itself up. If the switch is bad, then no clicky.

compressor clutch- check for power at the clutch, if there is power being sent there, then the clutch is bad.

fleetmgr

Huh? Don't think so...at least not in the last 80 years or so. The LP switch is there to govern the compressor so things achieve the design temperature, and nothing else. Has nothing to do with oil, which circulates freely thoughout the system.

OP, jump the clutch straight to the battery. If it engages, it's good. If it doesn't, it's bad.

If it does engage, and you have correct system pressure, then look for a vacuum leak. Start at the rear of the intake, where vacuum taps off to go to the blend doors in the heater box.

99345hp

yes, but it also there to keep the compressor from running if the charge is too low. If the charge is too low, there wont be enough oil running through the system to keep the compressor from locking up.

Id also like to know a car in the 30s that had ac.

fleetmgr

If that were the case, you wouldn't be able to run the system after charging it (assume a new system here) and not adding oil, but it'll run quite nicely until the compressor pukes. LP is an operational switch, not a safety switch.

99345hp

yes it will run nicely, but like you just said the compressor will puke. Since the oil is carried by the freon, without it there is no oil to lubricate the compressor so it will puke. The low pressure switch doesn't know if there is oil in there, just if there is adequate freon. It is just assumed that the correct amount of oil is in the system.

02WS6SSZ71

iTrader: (20)

fleetmgr

What's the difference between an A/C, a refrigerator, and a freezer all using R134a (or any other refrigerant, like R-12, R-502 etc)? If you'll look a P/T chart (http://highperformancehvac.com/hvac-...-refrigeration) you'll see that it's only the suction pressure. All other components in the system will be 100% identical (35 years of experience in commercial and automotive A/C & R tells me this). The only thing differentiating the three is the setting of the LP switch. None of them have problems with oil flow, even if the LP side goes into a vacuum. All the LP switch controls is evaporator temperature, and nothing more.

Dal1as

My bad. I meant the accumulator getting cold.