DIY AC R134a recharge writeup.

**SecretAznSauce** · 06-21-2007, 01:19 AM

its not that hard man

**noise boy** · 06-21-2007, 12:52 PM

+1 I got the gist of how it all comes apart, etc from searching in the forums. The work doesn't require any special tools other than the manifold set, and once you have that, you can fill your buddies rides for lunch money

. Taking it apart and putting it back together is just bolts and common sense, and the procedure for vaccuuming out the system and recharging it is here on the forums. A trick I learned from a pro, when filling the system put the can and valve in a bucket of warm water, as the can vents into the system the valve and such tend to freeze and the contents in the can shrink and lower in pressure due to the cold. The warm water counteracts that and allows you to completely drain the freon can.

Robert

**sbinplano** · 06-21-2007, 10:35 PM

Auto Zone will let you "borrow" a vacuum pump and gauges for 90 days. You do have to leave a $200 deposit on the pump and $100 on the gauges but they will refund those totally when you bring them back.

**qwfx** · 07-15-2007, 10:39 AM

I cant see the write up please fix, or can anyone tell me another link, whats the diference between the upper and lower caps,
thx

Originally Posted by SecretAznSauce

As with all DIY writeups. Proceed at your own risk.

It was 85 degrees today, and the secretaznman, thats me, can't stand heat too well. So I proceeded in recharging the bimmer.

you will need r134a freon, hvac gauge and about 25 minutes

first remove the inlet caps. the big one on the left is the High side. the small one on the right is the low side. Use ONLY the low side to charge with.

 <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4214_IMG.JPG"> See what your current charge is. Start your can on and turn the ac to max. Also note your engine needs to be at normal operating temperature. <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4216_IMG.JPG"> An over charged systems can also not cool. attach your gauge to the low side and then the high side, you should be around 25-35 psi on the low side and 160 - 185 psi on the high side. mine was around 20 psi and 140 psi. attach the freon can to the valve and attach to low side inlet. slowly open can and you should feel the can getting cold. this means the compressor is sucking in the freon. <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4215_IMG.JPG"> I added about 1 can of freon, but I am very familiar with ac systems, you should do half a can at a time and check your levels. My ac was cold at 25 psi low and 175 high <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4220_IMG.JPG"> <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4221_IMG.JPG"> at 48 degrees. it was cold enough for me <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4219_IMG.JPG"> if you have to add more than 1 can of freon, you might have a leak and so you will need to check that out. time for a test drive TTYL

**subzero32** · 07-15-2007, 11:00 AM

Originally Posted by SecretAznSauce

As with all DIY writeups. Proceed at your own risk.

It was 85 degrees today, and the secretaznman, thats me, can't stand heat too well. So I proceeded in recharging the bimmer.

you will need r134a freon, hvac gauge and about 25 minutes

first remove the inlet caps. the big one on the left is the High side. the small one on the right is the low side. Use ONLY the low side to charge with.

 <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4214_IMG.JPG"> See what your current charge is. Start your can on and turn the ac to max. Also note your engine needs to be at normal operating temperature. <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4216_IMG.JPG"> An over charged systems can also not cool. attach your gauge to the low side and then the high side, you should be around 25-35 psi on the low side and 160 - 185 psi on the high side. mine was around 20 psi and 140 psi. attach the freon can to the valve and attach to low side inlet. slowly open can and you should feel the can getting cold. this means the compressor is sucking in the freon. <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4215_IMG.JPG"> I added about 1 can of freon, but I am very familiar with ac systems, you should do half a can at a time and check your levels. My ac was cold at 25 psi low and 175 high <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4220_IMG.JPG"> <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4221_IMG.JPG"> at 48 degrees. it was cold enough for me <img src="http://www.dynamicautoworkz.com/cars/BMW%20325i/ac%20recahrge/142-4219_IMG.JPG"> if you have to add more than 1 can of freon, you might have a leak and so you will need to check that out. time for a test drive TTYL

Why do your links not work, are you expecting people to copy and paste ever line of text, mabey i'm missing something.

**BR Random** · 07-19-2007, 01:54 PM

Originally Posted by jwf1999

Im from america im just stationed overseas atm. But i was just putting a word of warning cause it would suck to be the one unlucky guy that gets hit up at an autozone for a $25 can of r134a and then realises he has to pay a $10k fine and thats no joke on the amount of the fine. The only reason i know all this is because i had to be epa certified for my job in the air force and they go over all the lil stuff like how much you get fined and all that.

So just talked to a buddy that works at autozone and my friend mark who works at Advanced and they pretty much both said that's full of S##T. Which tells me you were either misinformed or the people that sell the stuff were. And no offence but after serving for 5 years I know better than to believe anything the military tells you.

**BR Random** · 07-19-2007, 02:02 PM

Originally Posted by subzero32

Why do your links not work, are you expecting people to copy and paste ever line of text, mabey i'm missing something.

It's HTML code. Create a text dcoument, paste the code in, save it and change the extension to .html and you can view it. PS the images still won't work because the website they were hosted on is gone.

**RFtesla** · 07-21-2007, 08:01 PM

Could someone possibly post some new pictures since the old ones are now down? Thanks.

**jszy25** · 08-03-2007, 12:04 PM

Im interested in a pic as well....of the location where you hook up the recharge can.

**ecko457** · 08-03-2007, 01:03 PM

Just did this the other day, I really don't think you have to evacuate the system cause I didn't, but like said above use the low presure hose its the fatter one, if you stand in front of the car its the one to your right. I didn't use a gauge just the hose to fill it.

First I used r134 leak stopper and detector, it has die in it so if it doesn't stop the leak for you you know where the leak is, I did this just as a precautionary action, I had no leaks.

Filled it with two cans of r134 and vuala AC works again, I didn't use a half can at a time I just emptied um both.

**jszy25** · 08-03-2007, 01:59 PM

I have two connections...one close to the firewall and the other at the front of the engine bay close to the passenger side headlight. Does anyone know which one to fill at?

**WV Jim** · 08-03-2007, 02:19 PM

This past weekend, I went to Advance Auto and bought (for $19) a small cylinder of R134A with a hose and gauge attached. You start your car, turn the AC on high, hook the hose up to the low side (it's obvious which one that is - the only one the hose will hook to), and the gauge tells you everything you need to know. You push the button, turn the can sideways (to also put lubricant into the system) and in a few seconds it's recharged.

Simple and inexpensive.

I didn't read this entire thread, so I apologize if someone already brought this up.

**M///BMW** · 03-02-2008, 05:20 PM

bump please...i need some pics...

**kinghawk** · 03-02-2008, 05:49 PM

My A/C hasnt been working for a couple years and really want to get it fixed for this summer.

Issue is, there hasn't been any freon in the system for that time. Also my recirculation button light doesn't light up, but my A/C button does. Is that an issue I should be worried about?... is there a fix for the recirculation if it isn't related to the lack of pressure?

**richbarn2** · 03-02-2008, 06:07 PM

i noticed one thing that wasnt mentioned, when you are serviceing the system it is very important to keep the can upright so vapor is introduced to the system. if the can is accidentally flipped (with the valve down) you will be inroducing liquid freon which can/will damage the compessor.

also, anytime the system is opened it will need to be vacuumed for a couple reasons. it removes the moisture/humidity that was introduced while the system was open. it is also the correct way to leak check the system, close the vac valve and let the system sit. if the needle moves, you have a leak.

**mt_goat** · 03-21-2008, 04:27 PM

Ok. here's some pics from my 97 328i:

Low pressure port

High pressure port

**mt_goat** · 03-21-2008, 04:35 PM

Originally Posted by richbarn2

i noticed one thing that wasnt mentioned, when you are serviceing the system it is very important to keep the can upright so vapor is introduced to the system. if the can is accidentally flipped (with the valve down) you will be inroducing liquid freon which can/will damage the compessor.

I noticed in the auto parts store here they had some brands of R134 that said to hold the can upright, and another brand (Dupont) that said to hold the can upside down, and then another brand that didn't say which end to hold up. So I'm thinking that some cans draw from the top of the can and some draw from the bottom. And that may explain why that one guy only got it to work upside down. That's my theory anyway

**sebastianforbes** · 03-21-2008, 05:45 PM

well done mt goat...

great pictures... but would you believe that both of my ports are side by side ?!! the high is beside the low !

i only knew which one was low because it goes to the compressor.

**mt_goat** · 03-21-2008, 06:03 PM

Yeah I saw a pic of one side by side in this writeup:
http://forums.bimmerforums.com/forum...c+manifold+diy
Also I noticed that the low pressure port is smaller than the high side. And from one thread I saw that the filter/dryer is on the high pressure side.

I found after connecting a gauge to mine that after 11 years of never being serviced my system is still fully charged. I was hoping that I could just add a little juice and make it start cooling like my 95 Taurus. So I guess I'll look at changing my cabin filter as a solution. I may also try getting a high side gauge to see if the compressor is pumping good.

**noise boy** · 03-21-2008, 11:26 PM

Originally Posted by ecko457

Just did this the other day, I really don't think you have to evacuate the system cause I didn't, but like said above use the low presure hose its the fatter one, if you stand in front of the car its the one to your right. I didn't use a gauge just the hose to fill it.

First I used r134 leak stopper and detector, it has die in it so if it doesn't stop the leak for you you know where the leak is, I did this just as a precautionary action, I had no leaks.

Filled it with two cans of r134 and vuala AC works again, I didn't use a half can at a time I just emptied um both.

You don't necessarily have to evacuate the system, that is more an issue if you are going to open a charged system up to repair/replace something. I also have had pretty good luck with the DIY hose deal that comes with the can, as long as you have some freon, just topping it off is easy.

Robert

**noise boy** · 03-21-2008, 11:28 PM

Originally Posted by mt_goat

Ok. here's some pics from my 97 328i:

Low pressure port

High pressure port

Interesting on my car (93 325is) the high pressure port is right up next to the low pressure port in your picture at the fire wall. I guess at some point (new motor?) BMW changed that.

Robert

**Soviet1942** · 04-09-2008, 11:00 PM

The pictures are not working for the first post.

Also, for the picture above me. Is the high and low side in the same location on a '95 325i?
Lets say I didn't know where the high and low side were (because I plan on doing this for my GFs car), what would be a easy way for me to tell the difference?

Thanks

**Jimmie Jazz** · 04-09-2008, 11:28 PM

The fittings are different sizes- One is bigger than the other, and so are the corresponding hose connections. Its tough to get them wrong; go ahead and you'll see what I mean.

**Soviet1942** · 04-10-2008, 01:34 PM

Alright, coo.. Thanks for the info. And the larger size will always be the high side? On any car?

**jsflagstad** · 04-24-2008, 12:03 AM

So when the shops convert from r12 to r134 do they normally pull a vacuum on the system before recharging with r134. Aren't they supposed to get all of the r12 oil out? Will pulling a vacuum for the specified 30 mins get all of the r12 oil out or is there a way to drain it? The reason I ask is that I has my 92 325is (E36) converted, and I don't think that they pulled a vacuum on the system.

Anyone have some input?

JSF

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