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DISCUSSION => General Topics => Topic started by: Choking Hazard on May 02, 2006, 04:12:33 PM

Title: A/C retrofit. Are you cool?
Post by: Choking Hazard on May 02, 2006, 04:12:33 PM
Here in the sunny south, as the winter chill receeds (along with the ozone layer), my thoughts for this solar-collector DS paint center on what to expect in August (like 102 outside = who knows on the inside).  I have always been the family "minimalist" with no AC, electric windows, etc, but now I have a car that has an actual A/C system and I'm gonna use it!  Freon-12 is $50 a can and R-134 is known to impact R-12 compatible compressor seals.  Web searched into a product called "Hot Shot" R-414.  It isn't a propane based alternative, its about $10 a can, it is suppossed to work with existing hoses, seals, fittings, and the R-12 drier.  Anybody here familiar with this product?  If you are, and it is crummy stuff, please don't tell me (kidding...).  Thanks!
Title: A/C retrofit. Are you cool?
Post by: Febi Guibo on May 02, 2006, 04:29:32 PM
I think D Clay has some info on it... for everyone's sake, maybe he will chime in on it.
Title: A/C retrofit. Are you cool?
Post by: jfdublyu on May 02, 2006, 09:07:31 PM
i want to 134a, does anyone have a complete list of what all needs to be done for full and working conversion? i bought the "conversion kit" last summer which had just an adapter and some recharge cans, but this didn't work cause i know that seals need changing or something. i'm not to avid w/ a/c systems, just that it's supposed to be cold.
Title: A/c
Post by: D. Clay on May 02, 2006, 10:12:33 PM
I have 1992 318is with the Nippodenso compressor. I converted it by using a "kit" and a new drier. That was over two years ago and it still works as good as it did before with no leaks. It's a rare E30 with the original compressor - one without an A/C for a decade. It's probabaly been rebuilt since 1995.
 
http://www.napaonline.com/masterpages/NOLMaster.aspx?PageId=470&LineCode=BK&PartNumber=7652979&Description=A%2fC+R134a+Refrigerant+Recharge+%26+Retrofit+Kit (http://www.napaonline.com/masterpages/NOLMaster.aspx?PageId=470&LineCode=BK&PartNumber=7652979&Description=A%2fC+R134a+Refrigerant+Recharge+%26+Retrofit+Kit)

My neighbor is a real DIY'er. He made an A/C vacuum pump out of an old refrigerator compressor by soldering ends on the copper lines.
Title: A/C retrofit. Are you cool?
Post by: Choking Hazard on May 03, 2006, 04:46:46 AM
Quote from: jfdublyu
i want to 134a, does anyone have a complete list of what all needs to be done for full and working conversion? i bought the "conversion kit" last summer which had just an adapter and some recharge cans, but this didn't work cause i know that seals need changing or something. i'm not to avid w/ a/c systems, just that it's supposed to be cold.

What I have been reading and what the guy at the local A/C place (who quoted $300 to change JUST fittings and charge with r-134), there is really no practical or at least easy way to change the compressor seals.  He said it would work for "awhile".  That was one of the reasons I did not go the r-134a route.  This r-414 stuff is supposed to be fully compatible, etc.  That said, if your compressor functions and the system is fully charged with r-134, I would think it should work.  Did you replace the "drier"?  I understand that is needed with the r-134 conversion.
Title: A/C retrofit. Are you cool?
Post by: dbgrubbs on May 03, 2006, 07:32:54 AM
Why not go with Freeze 12? It's compatible with the stock system and is available on ebay. My local AC guy put it in my Alfa and I've been running it for 2 years now with no problems. Just as cold as R-12.
Title: A/C retrofit. Are you cool?
Post by: sheepdog on May 03, 2006, 04:04:30 PM
A second for Freeze12. it is the way to go.


$50 gets you a kit to do it yourself. No need to replace anything (they recomend dong the dryer), plus it is cheap.

Downsides to R-134, costly, and tends to lock up the compressor after a year or so since the lubricant is not compatible.


My Freeze 12 has been in over a year without a hickup.
Title: A/C retrofit. Are you cool?
Post by: sheepdog on May 03, 2006, 04:05:50 PM
By the way, I say the conversion kit for R134 the other day, to do it yourself, it was 30-$60 and comprised of about 30+ o-rings. It requires A LOT of work, including disassembling the pump.
Title: A/C retrofit. Are you cool?
Post by: jfdublyu on May 03, 2006, 05:09:27 PM
does anyone have the part number for the dryer? how much did you pay for it? do it yourself?
Title: Compressor oil.
Post by: D. Clay on May 03, 2006, 05:46:50 PM
Most kits have oil with them that mixes with the old type and makes it compatible with the new stuff. It's not the type of freon, it's the type of oil that is the problem. There's not much too lose.  The first recharge saves money.
Title: A/C retrofit. Are you cool?
Post by: Wizard on May 03, 2006, 06:36:29 PM
If you have a Denso compressor you should be good to go as these are suppose to be 134 compatible mine was actually marked on the lable as R-134 compatible.....But you have to remove the compressor and drain all the oil out of it. Then refill it with PAG 150 oil. You also have to change the dryer. Usually you can pick up a new one on ebay pretty cheap. You will also need the retrofit valves which are included in the kit (which includes the 134) you can pick up at Wally-World...
One word of warning though.....I know on my 91 318is, the low pressure side line runs close to the top of the fender and with the extra lenght of the new 134 fitting I sometimes have trouble opening the hood. The hood must be hitting the top of the cap and putting pressure on it. I heard they make 90 degree fittings so it doesn't sit so high, but haven't looked for them yet.
Title: A/C retrofit. Are you cool?
Post by: sheepdog on May 03, 2006, 10:36:45 PM
Honestly, when I did mine, my system was VERY empty. I just depressurized what was left and started filling. As it filled, I bled off some from the high side to remove what I could.

I changed nothing.


I paid about $50 for the kit, which came with lube, and leak detector and a guage as well as the freon, and started putting it in.  Took around an hour or so. Been used quite a lot.

I do not recomend following what I did, but it worked fien for me. Granted, my pump could go tomorow, but I will deal with that when the time comes. If it does, even after I buy a new pump and some fresh cans of Freeze 12, and a dryer, I should still be ahead of the game compared to getting a r12 refil.
Title: A/C retrofit. Are you cool?
Post by: jfdublyu on May 03, 2006, 10:41:53 PM
yeah, i already have the retrofit from wally-world, but i have a problem that is keeping me from truly testing the A/C: I'm missing the middle v-belt, the one that runs the A/C! I need to get a belt, but it's not that hot yet so i will wait
Title: A/C retrofit. Are you cool?
Post by: jfdublyu on May 03, 2006, 10:58:55 PM
ok, im trying to find the dryer on ebaybut the part #s don't match realoem.com for the '91. i found a few dryers for the earlier e30's (84-89), but none for 90-91. What gives? are they different at all or can I just use one from an '89 325?
Title: A/C retrofit. Are you cool?
Post by: Choking Hazard on May 04, 2006, 08:06:28 AM
Well. I had already purchased the r-414 when I first posted.   But like Freeze-12, other than fittings, nothing is changed so if it does not work I'll not have mucked it up further.  In fact, the web site indicated no drier change either.  Did you fellers using FR-12 change the drier?  I wonder why it is need with 134?  Is that where the oil accumulates?  Anyway, when the r-414 kit arrives and I try it out, I'll report my results...
Title: A/C retrofit. Are you cool?
Post by: Wizard on May 04, 2006, 02:29:48 PM
According to the Advance Auto Parts website the same Accumulator/Filter Drier fits all these models:
        Part Number: 33444

   1985 318I
   1987 - 1991 325I
   1991 318I
   1987 - 1993 325IC
   1991 318IC
   1987 - 1991 325IS
   1991 318IS
   1988 - 1991 325IX
   1987 - 1988 325
   1988 - 1991 M3
   1986 - 1987 325E
Title: A/C retrofit. Are you cool?
Post by: M42boy on May 04, 2006, 03:37:03 PM
Quote from: dbgrubbs
Why not go with Freeze 12? It's compatible with the stock system and is available on ebay. My local AC guy put it in my Alfa and I've been running it for 2 years now with no problems. Just as cold as R-12.

Hey Don...  what exactly is Freeze 12?  

I know "freon" as we know it (R-12) is very expensive now, but I actually prefer it to R134A as it's a better and more efficiant refrigerant.  Of course, you can buy R234A anywhere and it's cheap!  But, if our cars aren't R134A, it's a PITA to convert.  I guess if my compressor dies, I'd try to upgrade to a complete R134A system, but otherwise, I'd rather just find a cheap refrigerant that will work with my current R12 system since I think it still works fine.
Title: A/C retrofit. Are you cool?
Post by: sheepdog on May 04, 2006, 05:02:23 PM
Quote from: M42boy
Hey Don...  what exactly is Freeze 12?  

I know "freon" as we know it (R-12) is very expensive now, but I actually prefer it to R134A as it's a better and more efficiant refrigerant.  Of course, you can buy R234A anywhere and it's cheap!  But, if our cars aren't R134A, it's a PITA to convert.  I guess if my compressor dies, I'd try to upgrade to a complete R134A system, but otherwise, I'd rather just find a cheap refrigerant that will work with my current R12 system since I think it still works fine.

From what I have read, basically it is 134 blend with a universal lubricant. It also has something that makes the r134 work at lower pressures. Freeze12 actually operates at lower pressures than r12 even.
Title: A/C retrofit. Are you cool?
Post by: bmwsmurf on May 07, 2006, 01:23:03 AM
Don't you have to vacuum out all the air out of the system first if your AC hasn't worked in a while?
Title: A/C retrofit. Are you cool?
Post by: sheepdog on May 07, 2006, 02:56:42 PM
Quote from: bmwsmurf
Don't you have to vacuum out all the air out of the system first if your AC hasn't worked in a while?

Vacuuming is primarily to make sure there is no r12 or water in the system.

Air will have moisture in it, but again, for the money, if it fails later, oh well, I will just convert to full r134.