DIY AC Recharge Kit?

[Brent824]

My AC doesn't seem to be a cool as it should be. What are your opinions on do it yourself AC recharge kits that can be purchased at auto parts stores? Are these effective/safe/easy to use?

Thanks!

[unity]

Well first you need to know one thing. AC systems should never become less effective, ever. Coolant does not get weaker, etc.

So if its not up to par, there is a leak. Keep that in mind if you do one of these kits.

Yes they work. I have used them in the past. In WI one can not buy the cans of R134a so I get them shipped up from Chicago. I replaced all the seals on mine but I found a leak caused by rust and will be doing this again.

[HOTLNC]

My AC doesn't seem to be a cool as it should be. What are your opinions on do it yourself AC recharge kits that can be purchased at auto parts stores? Are these effective/safe/easy to use?

Thanks!

What does the "kit" include?

[whiplash15]

The better ones come with the required hose and gage, the proper adaptors and somme freon. Read the directions carefully - dont let "simple" cause you to trip, and dont over fill.

[Brent824]

Thanks for all the help!

[HOTLNC]

The better ones come with the required hose and gage, the proper adaptors and somme freon. Read the directions carefully - dont let "simple" cause you to trip, and dont over fill.

I've always wondered how one determines "overfill." The big boys do it by weight (filling empty systems.) But what about a partially filled system? Can you do it by pressure and temperature?

[driller]

...Can you do it by pressure and temperature?

I'm sure you can. I know with the older systems, you could do it with just guages and temperature probe.

[MindyMark]

But what about a partially filled system? Can you do it by pressure and temperature?

Yes you can but I don't feel it is as accurate unless you are using a gauge set with a high side connection rather then the low side only connection found in the DIY kits.

If you only have a low side gauge and are going by temp and pressure it should be around 55 to 65 pounds of pressure on the low side at idle was 70 degrees outside. This would correlate to around 40 to 50 degrees for the system temp. (of course all of this is without looking at an actual gauge). The compressor should be running almost non-stop at this point.

But there are so many variables (engine speed, outside temp, freon charge) that's why I prefer to use the high side as well which will hover just over 300 psi when fully charged and operational.

In addition to getting a proper charge by monitoring the high side you can also verify there is nothing else wrong with the system, such as a blocked orifice tube. Which if you were charging only on the low side you wouldn't be able to see until you blew the over pressure valve.

[MindyMark]

My AC doesn't seem to be a cool as it should be. What are your opinions on do it yourself AC recharge kits that can be purchased at auto parts stores? Are these effective/safe/easy to use?

Thanks!

To answer the original question, they can be if used properly. As others on this forum have said, A/C's don't just stop working because of age. When was the last time you added freon to your fridge just because?

There is something wrong with the system or freon has leaked out. So fix the leak first. :-)