AC Recharge

[LJS30]

Hey gentlemen my 01 needs to have the AC recharged so I pose this question to you. I have heard from several mechanics that the recharge canisters you get from Autozone, O'Reilly's, etc....actually aren't so hot for the system overall. Is their any truth behind this?

 

[LS4me]

First find out why you need a recharge.

 

[Blueberryyum02]

Did you check to see if the fan is spinning up to high mode.
2001-2002 have hydrolic driven cooling fans the acuator on them fails to open for high speed check that first. Also do you notice if it's running hotter then normal or over heating.

 

[LJS30]

Well I just swapped the degas bottle, t-stat, cap, some hoses going to the bottle, and had the system bled. The AC was already having issues blowing cold and I never had a real overheat situation in terms of the car going in limp home mode or even hitting the hot on the gauge.

 

[joegr]

Hey gentlemen my 01 needs to have the AC recharged so I pose this question to you. I have heard from several mechanics that the recharge canisters you get from Autozone, O'Reilly's, etc....actually aren't so hot for the system overall. Is their any truth behind this?

There are two problems here.
1. You need to use a set of pressure gauges and monitor the high side and low side pressure at the same time. You can't accurately fill the system without seeing both pressures and comparing to a chart of desired pressures vs temperature. Just filling by the low side color coded pressure gauge on the can is not a great idea.

2. Most of the cans (just about all of the ones with a hose already attached) contain additives in addition to the R-134a. Except for a little compressor oil, you don't need or want these additives. At best, they don't do anything (meaning that you have less R-134a working for you to cool you off). At worst, they may clog the expansion valve.

It is important to find out why you are low on refrigerant in the first place. If it's just several years of normal out-gassing through the hoses, then that's okay and all you need is really just to add the correct amount of refrigerant and a little oil. One the other hand, if the compressor is leaking or some other low spot on the system, then you have probably lost just about all of your oil already. In this case, if you just top up the refrigerant and don't replace all the lost oil, your compressor will self destruct after a while and you will now need to flush the whole system and probably replace the expansion valve (this is expensive because the whole dash will have to come out to do it).

 

[LJS30]

Thanks for the input Joegr.