Has anyone "recharged" their AC? Anyone use this?

Hello,
My AC is OK in my car, but my friend is driving up from Virginia and told me she ran out of freon in her car. It got me thinking about the AC in my own car, and realized I know nothing about BMW AC. Does this sytem use freon? Does it have to be maintained? Topped off? 134, 134a, etc...? I just watched this youtube video:

The guy in the video used Interdynamics Arctic Freeze Ultra Synthetic R-134a Recharge Kit with UV Dye. Has anyone on here done this? Is is BMW ok?

A/C systems typically need zero maintenance. If you are low on refrigerant, you have a leak that needs to be repaired. R-134a can be a little temper-mental, due to it's expansion rate. The only way to get optimum performance is to charge the system by weight, which requires an A/C machine. The M3 holds 740 grams, or 1.63lbs. Not the smallest system, but still small enough to easily overcharge. In this system, an overcharge will develop the exact same symptoms as an undercharge in hot weather. The hotter the ambient temp, the lower the cooling capacity.

With that said, can you do it with this method? Sure.

I did it worked fine as my car was parked a few years before I bought it.

Usually a good check is vent temps. Stick a thermometer in the vents and read with the AC on full.

With Freon, the temp would be about 32-34 degrees. The R-134a is not a cold, maybe 45 degrees, depending on outside temp, but I don't have a spec chart for the M3. Anyone?

If you are reading high, you may need a recharge.

Did this recently with my car. The seals on the compressor get old after a couple years and start to slowly leak not really a big deal, i recharged the system a couple months ago and it's still working fine.

AC systems are completely closed loop. Which means if you need a recharge you have a leak - which in turn means you need to fix the leak rather than just dumping freon in there periodically. DO NOT use any of the "liquid sealer" products as you will regret it.

I did this recently with great results. Bought a gauge that has a freon can port. Hooked up the gauge first. Saw that it could use some freon. screwed in the can and shook until empty. close the valve and saw I still had room for more freon but chose to leave as is and assess. A/C worked much better. I'm happy.

BTW - follow directions. Car has to be running. And you can easily connect and disconnect the gauge with the car running. I turned the car off with the gauge connected and the pressure goes up quickly. I feared the system was over pressurizing. It isn't . It's pressure increase in the short leg of the port.

I've used this once on my e46 325i but not yet on my M3. Ac worked great for 3 yrs with no recharging.

I had a leak and used it in June of last year after replacing the hose. AC has work great ever since!








Found the leak!!

Originally Posted by TKC

I had a leak and used it in June of last year after replacing the hose. AC has work great ever since!








Found the leak!!

Can you point me to where you found your leak?

Thanks