BMW E24 AC upgrade(AS OF 2016)

[flyfisherman]

So did BMW ever put a good A/C system in any of the sixers?

Yes, beginning with the 2003 model year 6 series. BMW and Porsche did not believe in functional A/C in the 1980s.

[dcains]

My '88 E30 had a/c that would chill beer, and I'm in S. Florida. The '85 535i and '88 M5 I also had back in the day (and both were black) had terrible a/c, and that's why I didn't keep either one even a year. Never had a 635 until July 2014, and all those sweaty memories came flooding back. The a/c in the E24 really seems like an afterthought.

[carmel by the s]

Thank you for this thread !

can someone please be very specific on an A/C upgrade parts list and what is fully needed to do it correctly.
this would be for non OEM BMW parts, what aftermarket parts are needed to do this.

1. Parts list and location to purchase the parts, also bracket

thank you,

[hakeem43020]

Never thought I'd meet someone else who hated the AC as much as I do. I work outside so and live 30 minutes away so it's not a pleasant drive. I knew of this in the past and put it off for the longest while and now it's come back to bite me. I bought the eBay Condensor, brackets and plan on buying the drier($100 because of the rear AC) then the compressor and get the hoses custom made.

Anyone know a cheaper alternative to the $110 drier?

Thank you for this thread !
A
can someone please be very specific on an A/C upgrade parts list and what is fully needed to do it correctly.
this would be for non OEM BMW parts, what aftermarket parts are needed to do this.

1. Parts list and location to purchase the parts, also bracket

thank you,

No problem. I haven't installed and tested the parts yet so at this point I'm not 100% sure. The compressor and Condensor will require custom brackets.

1.You'll need a 16 x 19 or 16 x 20 parallel flow condenser.
These are the ones others have used, not sure about other sizes. The ones you find will more than likely will not be a direct fit so you'll need brackets from home depot or lowes to get it to fit.

2. Some have said the condenser upgrade is more than enough but others also decided to upgrade the noisy compressor that comes with the car with Sanden 508 style compressors. These are not a direct fit and will require custom brackets. For those of you who are interested email willnolan00@gmail.com for a set. I got mine from him for $50.

3. It's recommended you replace your drier and front and rear expansion valve. To replace the front expansion valve you'll have to pull out the center console and it's a PITA. You can get by without replacing it but it's recommended to at least replace your drier, especially if you're converting from R12 to R134 or vice versa.

Then you have to get the hoses custom made.

I haven't done it yet so no pictures as yet but I'll upgrade this thread when my condensor gets here.

[demetk]

Some have said the condenser upgrade is more than enough but others also decided to upgrade the noisy compressor that comes with the car with Sanden 508 style compressors. These are not a direct fit and will require custom brackets. For those of you who are interested email willnolan00@gmail.com for a set. I got mine from him for $50.

Last time I spoke with him the brackets were available for $35. Looks like I'll be looking for a cheaper place to make them.

- - - Updated - - -

And just in case anyone is interested in R152 and what you can achieve in terms of sanden compressor performance and corresponding vent temps, http://www.mye28.com/viewtopic.php?f...81698#p1381817

[hakeem43020]

Last time I spoke with him the brackets were available for $35. Looks like I'll be looking for a cheaper place to make them.

- - - Updated - - -

And just in case anyone is interested in R152 and what you can achieve in terms of sanden compressor performance and corresponding vent temps, http://www.mye28.com/viewtopic.php?f...81698#p1381817

Wish I had other alternatives at the time, everyone else I knew stopped making them so I stuck to him . Hopefully others can get it for a cheaper price and no way, you got blended air in your e28? I thought I was the only one who was ticked off by our cars not having it. Never heard of r152 until now, what's advantages have you noticed over r12 and r134a? I'm definitely adding this to my to do list for my e24.

[demetk]

Wish I had other alternatives at the time, everyone else I knew stopped making them so I stuck to him . Hopefully others can get it for a cheaper price and no way, you got blended air in your e28? I thought I was the only one who was ticked off by our cars not having it. Never heard of r152 until now, what's advantages have you noticed over r12 and r134a? I'm definitely adding this to my to do list for my e24.

Yeah, it looks like the price went up for some reason. This bracket project was supposed to be a non-profit undertaking as a way of giving back to the BMW community from which I learned so much from. dcains was very gracious to take the bracket drawings to a machine shop where he had them made. He successfully completed a number of non-profit group buys for us. My thanks to him for freely giving his time to this whole endeavor.

I do have a kind-of-blended air hvac in my e28 now. Feel free to read up on it in that thread I posted. Bear in mind that the fuse boxes between the e28 and e24 are different and that means different fuses as well as slightly different circuits are used to power the respective systems.

R152 is interesting as it has similar characteristics to R12 at a fraction of the price. As we all know R12 is the preferred freon to use as it is much superior to r134 given the limited size of the condenser we can install in our cars. Some have mitigated the condenser size limitation by installing 2 condensers in parallel, one behind the other, and then r134 becomes more viable as an alternative refrigerant. What you get with R152 is reduced high side compressor pressures and much better cooling than with R134. I can hardly notice the compressor turn on now. And it does look like R152 will the next replacement when R134 is phased out in a few years. A much more knowledgeable discussion of R152 is here, http://www.rx7club.com/2nd-generatio...gerant-964688/

I charged my e28 with 3 cans for a total of $10 spent. From some research, you'll find that you charge R152 at 62% of the R12 charge. I did 3 cans but I may be slightly overcharged based on that. I'm going to see what the sub-cooling is with this charge and that should tell me whether I need to remove or add charge to get me to an estimated 10 degrees sub-cooling. I charge my home hvac systems via sub-cooling and there are discussions on the a/c forums that indicate you can do the same to car hvac. And here is a side-by-side temp/pressure chart for R12, R134 and R152 http://www.rx7club.com/attachments/2...a-tp-chart.pdf

This is a nice discussion you guys are having here. It makes me miss my e24.

[hakeem43020]

Yeah, it looks like the price went up for some reason. This bracket project was supposed to be a non-profit undertaking as a way of giving back to the BMW community from which I learned so much from. dcains was very gracious to take the bracket drawings to a machine shop where he had them made. He successfully completed a number of non-profit group buys for us. My thanks to him for freely giving his time to this whole endeavor.

I do have a kind-of-blended air hvac in my e28 now. Feel free to read up on it in that thread I posted. Bear in mind that the fuse boxes between the e28 and e24 are different and that means different fuses as well as slightly different circuits are used to power the respective systems.

R152 is interesting as it has similar characteristics to R12 at a fraction of the price. As we all know R12 is the preferred freon to use as it is much superior to r134 given the limited size of the condenser we can install in our cars. Some have mitigated the condenser size limitation by installing 2 condensers in parallel, one behind the other, and then r134 becomes more viable as an alternative refrigerant. What you get with R152 is reduced high side compressor pressures and much better cooling than with R134. I can hardly notice the compressor turn on now. And it does look like R152 will the next replacement when R134 is phased out in a few years. A much more knowledgeable discussion of R152 is here, http://www.rx7club.com/2nd-generatio...gerant-964688/

I charged my e28 with 3 cans for a total of $10 spent. From some research, you'll find that you charge R152 at 62% of the R12 charge. I did 3 cans but I may be slightly overcharged based on that. I'm going to see what the sub-cooling is with this charge and that should tell me whether I need to remove or add charge to get me to an estimated 10 degrees sub-cooling. I charge my home hvac systems via sub-cooling and there are discussions on the a/c forums that indicate you can do the same to car hvac. And here is a side-by-side temp/pressure chart for R12, R134 and R152 http://www.rx7club.com/attachments/2...a-tp-chart.pdf

This is a nice discussion you guys are having here. It makes me miss my e24.

I appreciate you and dcains giving back to the community, think I see you guys on every forum I visit lol. Your post and has managed to grab my full attention and I see you got amazing results. What's your AC setup like? You mentioned you have a new compressor so I imagine your using the sanden 508 with or w/o a parallel flow condensor?

I remember reading a while back that someone replaced the AC blower fan with the heater blower fan and after looking at a few pics of the 2 they seem really similar. I would think that because they are sold separate they have different part #s and would not be interchangeable. Does this sound ridiculous to anyone else?

[demetk]

I'm running the sanden 508 compressor (http://www.ebay.com/itm/371644764398...%3AMEBIDX%3AIT) and a 16x18 parallel flow condenser from ACKits.

You should be able to fit a bigger condenser especially if you use Short Drop fittings like these,


If you're interested in making your own hoses then this crimper is great for that, https://www.amazon.com/Mastercool-71...productDetails

If you're system is evacuated, now would be a good time to checkout your evaporator and clean it out.
I'm glad I did because what I found was a bit horrifying,



And a correction is needed to how much you would charge with R152 vs R12.
The molecular weight of R152a is 68 and the molecular weight of R12 is 120.
The R152 charge would be 68/120=.56 the R12 charge.

[n2bimmer]

This thread delivers. Thank you all

[hakeem43020]

I'm running the sanden 508 compressor (http://www.ebay.com/itm/371644764398...%3AMEBIDX%3AIT) and a 16x18 parallel flow condenser from ACKits.

You should be able to fit a bigger condenser especially if you use Short Drop fittings like these,


If you're interested in making your own hoses then this crimper is great for that, https://www.amazon.com/Mastercool-71...productDetails

If you're system is evacuated, now would be a good time to checkout your evaporator and clean it out.
I'm glad I did because what I found was a bit horrifying,



And a correction is needed to how much you would charge with R152 vs R12.
The molecular weight of R152a is 68 and the molecular weight of R12 is 120.
The R152 charge would be 68/120=.56 the R12 charge.

The short drop fitting should allow a much bigger Condensor to fit. Currently have no way to measure since I haven't pulled it out but the next size up that I see would be a 16 X 23. Already ordered the 16 X 19 but I'm now tempted to try this.

Thanks, I recently cleaned my evaporator and lubed my AC fan since it was squeaking. I'm surprised your compressor is so cheap. I'm guessing that since it uses the SANDEN 508 mounting style my brackets would still work. Would these work in e24s too? I originally planned on getting this one http://m.ebay.com/itm/Vintage-Air-Sa...-/390969520521 but yours is much cheaper. Is there any significant difference between the two?

[demetk]

I've had good results with that ebay seller. I installed one of his compressors into my e34 and it's been working great for over 3 years now. Since then I've bought another 4 compressors from him and they've all worked great. Bear in mind these are sanden 508 type compressors made in china. I can't tell what kind of 508 compressor the one from vintage air is. Maybe it's a true sanden brand.

I'm assuming you have or will be flushing out the entire system?

[Mason Jones]

I appreciate you and dcains giving back to the community, think I see you guys on every forum I visit lol.

Amen to that!

I remember reading a while back that someone replaced the AC blower fan with the heater blower fan and after looking at a few pics of the 2 they seem really similar. I would think that because they are sold separate they have different part #s and would not be interchangeable. Does this sound ridiculous to anyone else?

I seem to remember reading that in a thread somewhere and they said the size of the motor is slightly different and they had to add some padding? And of course the plastic cages have to be swapped. I have them both out along with the evaporator housing and can try to fit it this evening. Edit: Turns out this is not true at all and I have no idea where I got that from! The 2 motors (at least on my 1985) are the same size with the difference being the plastic cages.

But there is also the issue of the sides of the fan housing being blocked by the sides of the center console which may make more of a difference to air flow than the fan motor: http://www.bimmerforums.com/forum/sh...le-and-A-C-fan

[hakeem43020]

I've had good results with that ebay seller. I installed one of his compressors into my e34 and it's been working great for over 3 years now. Since then I've bought another 4 compressors from him and they've all worked great. Bear in mind these are sanden 508 type compressors made in china. I can't tell what kind of 508 compressor the one from vintage air is. Maybe it's a true sanden brand.

I'm assuming you have or will be flushing out the entire system?

Yes, I planned on flushing it out. After vacuuming the AC down what else would need to be done to flush the entire system and I'll see if I can find difference to compare the two compressors because they look similar. Were you the one who fabricated your hoses? If so how hard was it? I planned on letting a shop do it but I'm willing to do it myself if it's not too hard.

Amen to that!

I seem to remember reading that in a thread somewhere and they said the size of the motor is slightly different and they had to add some padding? And of course the plastic cages have to be swapped. I have them both out along with the evaporator housing and can try to fit it this evening.

But there is also the issue of the sides of the fan housing being blocked by the sides of the center console which may make more of a difference to air flow than the fan motor: http://www.bimmerforums.com/forum/sh...le-and-A-C-fan

Thanks, please report back your results. If they are compatible it should significantly increase the airflow. I recall dcains posting that link in the beginning of this thread, forgot all about it. Maybe that's the reason for the insufficient airflow from the vents.

Does anybody else get air coming through the vents when driving fast with the AC and heat off? I'm guessing this has something to do with the "flapper valve" or something like that?

And for those of those who are reading and want an idea of what demetk meant about the double condensers here's some pictures I found on another forum.
Double condensor



and here's one with the single condenser



You can see that there's alot more space left on sides of the condenser but it's limited by the size fitting on the left which is why he recommended the short drop fittings to allow for a bigger condenser.

I'm really overwhelmed with all the responses and feedback shared in this thread. I remember seeing retrofits for these AC systems a few years ago but they all either went out of business or no longer have the parts. Thanks guys I really appreciate it.

[demetk]

Yes, I planned on flushing it out. After vacuuming the AC down what else would need to be done to flush the entire system and I'll see if I can find difference to compare the two compressors because they look similar. Were you the one who fabricated your hoses? If so how hard was it? I planned on letting a shop do it but I'm willing to do it myself if it's not too hard.

Here's my quick and dirty procedure that I used to charge my e28. The reason I say that is because I did not remove the expansion valve and flush the evaporator separately. I strongly suggest you do that because the expansion valve could be clogged and may still not work optimally afterwards, and that would necessitate removal and replacement after the fact.

In short this is the process I used.

1. flush the condenser with mineral spirits. I used a HF pressure bottle that I filled half way with mineral spirits and pressurized it with my compressor. I then disconnected both lines to the condenser and I then injected the flush it into one line and waited for the flush to run out the other. None did so I filled the bottle again repeated the flush. The flushing agent started to pour out the other end into a large jar I had handy. Once finished with the flush, I blew compressed air into the same line and kept blowing air through the system until the air came out the other end dry and free of any mineral spirits.

2. flush the evaporator with mineral spirits. Here I took the lazy way out and didn't remove the expansion valve first. Instead I back flushed the evaporator and a lot of crud came out. I then repeated the process by forward flushing the evaporator. Then I dried out the evaporator again with compressed air.

3. emptied the compressor of the existing mineral oil. Then poured a couple of ounces of pag 150 oil into the compressor, turned it over a couple of times to get the oil distributed well and then poured the oil out.

4. installed a new dryer. Before I connected the lines I poured about 3 oz of pag 150 oil into the dryer.

5. filled the compressor with 3 oz of pag oil.

6. made all the connections and turned the compressor over a few times so as to make sure I didn't hydro-lock it.

7. filled the system with 1 can of R152 on the low side port with the engine off.

8. started the car and filled it with the remaining cans.

9. checked pressures throughout and was surprised to see the compressor running a high side pressure of about 140 psi. With r134 the high side presser was more like 200 psi at idle.

Rebuilding hoses is very easy if you can use off the shelf fittings that you can buy online. Then all you need is some proper sized hose, a couple of fittings and the crimp tool. A simple hose would take you about 30 minutes to make. If you need to attach some other type of weldable fitting on to an existing a/c pipe then the process unfortunately becomes a bit more complex because of the tools and skills that you will need to acquire. Here's a brief example from an expert using sil-phos brazing rod: https://www.youtube.com/watch?v=1sdpOnV6dFQ. Be prepared to destroy a number of fittings in your search of experience. And since I pretty well DIY everything I get my hands on, there are a few redos along the way.

[IB635]

This is good stuff.. Just wondering, if one were to go with a parallel condenser AND R12, would you get super cooling??

[hakeem43020]

Here's my quick and dirty procedure that I used to charge my e28. The reason I say that is because I did not remove the expansion valve and flush the evaporator separately. I strongly suggest you do that because the expansion valve could be clogged and may still not work optimally afterwards, and that would necessitate removal and replacement after the fact.



Rebuilding hoses is very easy if you can use off the shelf fittings that you can buy online. Then all you need is some proper sized hose, a couple of fittings and the crimp tool. A simple hose would take you about 30 minutes to make. If you need to attach some other type of weldable fitting on to an existing a/c pipe then the process unfortunately becomes a bit more complex because of the tools and skills that you will need to acquire. Here's a brief example from an expert using sil-phos brazing rod: https://www.youtube.com/watch?v=1sdpOnV6dFQ. Be prepared to destroy a number of fittings in your search of experience. And since I pretty well DIY everything I get my hands on, there are a few redos along the way.

thanks for the detailed explanation and all your help. You've been really helpful. Since you used pag oil I'm guessing it's compatible with both r134 and r152. Ester oil is compatible with r152 right? I'll be getting the compressor and drier next week. Many have used the early e24 driers with good results so that should save me like $100. I realize your using the 2 groove compressor, is it just one groove that is used?

This is good stuff.. Just wondering, if one were to go with a parallel condenser AND R12, would you get super cooling??

Was wondering this as well.

To to everyone who's gotten the SANDEN 508 compressor, which one did you use?will Any double or single groove compressor work?

[demetk]

Yes, on the double v-groove compressors you would use the outer pulley. Here's is why you would use the outer groove pulley on the m30. It was discovered that if you attach the compressor with the left mounting ear of the compressor touching the oem mount like so, and build a spacer to fill in the gap on the right,



then the outer pulley will line up nicely with the engine pulley,



You also need to drill out the oem hole from m8 to 3/8" so you can use a 3/8" threaded rod to mount the compressor.

Here I ground out the mount a bit to facilitate tightening up the 3/8" nut,



Once the compressor is mounted on the oem mount then it's just a simple task of attaching the brackets to the lower ears of the compressor with m10 bolts and washers to get this spacing,





I don't remember if I documented the belt size I used but I can check if needed.

Based on the above, I have no idea how a single groove pulley compressor would facilitate fitment. My guess is that it would be more difficult to fit since the inner pulley on the 2 pulley compressor doesn't line up with the engine pulley.

[hakeem43020]

Thanks so much for the detail write up with pics. Will refer to this when I get my compressor and these compressors use a different belt size than the stock compressors?

[dcains]

This is good stuff.. Just wondering, if one were to go with a parallel condenser AND R12, would you get super cooling??

The E24 system has a few limitations. One of the biggest is the lack of airflow thru the vents. Having said that, the cooler you can get the air, the better you'll be. R12 will be much better than R134a, but I can't say it's a big difference from the R152, which I haven't tried yet. Big advantage with R152 is cost and availability, as well as less strain on the system due to lower operating pressures. I've got a nice stash of R12, but next time I have my system open, which I'll need to do for some other issues, I'm going with R152. I'll probably do the same with my '92 Alfa Spider.

[n2bimmer]

Yes, I planned on flushing it out. After vacuuming the AC down what else would need to be done to flush the entire system and I'll see if I can find difference to compare the two compressors because they look similar. Were you the one who fabricated your hoses? If so how hard was it? I planned on letting a shop do it but I'm willing to do it myself if it's not too hard.



Thanks, please report back your results. If they are compatible it should significantly increase the airflow. I recall dcains posting that link in the beginning of this thread, forgot all about it. Maybe that's the reason for the insufficient airflow from the vents.

Does anybody else get air coming through the vents when driving fast with the AC and heat off? I'm guessing this has something to do with the "flapper valve" or something like that?

And for those of those who are reading and want an idea of what demetk meant about the double condensers here's some pictures I found on another forum.
Double condensor



and here's one with the single condenser



You can see that there's alot more space left on sides of the condenser but it's limited by the size fitting on the left which is why he recommended the short drop fittings to allow for a bigger condenser.

I'm really overwhelmed with all the responses and feedback shared in this thread. I remember seeing retrofits for these AC systems a few years ago but they all either went out of business or no longer have the parts. Thanks guys I really appreciate it.

When replacing the condenser, do you remove the radiator? or work from the bottom, our cars dont have all that open space up front. Thanks

[dcains]

From the bottom. More trouble if your car has the oil cooler, like mine, but not too bad. I also took the grilles and headlight assemblies out.

[n2bimmer]

From the bottom. More trouble if your car has the oil cooler, like mine, but not too bad. I also took the grilles and headlight assemblies out.

How would you mount the brackets up top, from the bottom, i guess i haven't looked carefully

[dcains]

That's why I pulled the grilles and headlights. Just takes a few extra minutes, and allows much easier access to the bolts, fan, wiring, hose fittings, etc.

[n2bimmer]

That's why I pulled the grilles and headlights. Just takes a few extra minutes, and allows much easier access to the bolts, fan, wiring, hose fittings, etc.

Makes perfect sense, thanks.