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Dash Air Refrigerant

July 30, 2018, 06:48:44 pm

On a 1989 U300, would the Dash Air use R-12 or R-134?

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Re: Dash Air Refrigerant

Reply #1 – July 30, 2018, 06:55:59 pm

R 12 
What do the service hose connections look like?
Screw on or quick connect?
If quick connect them system probably has been converted to 134a

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Re: Dash Air Refrigerant

Reply #2 – July 30, 2018, 07:07:36 pm

Thanks. I hope not, but I'll check the connections. R-12 is much better cooling wise.

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Re: Dash Air Refrigerant

Reply #3 – July 30, 2018, 07:12:33 pm

I'm not sure that you can get R-12 anymore as it is illegal (I'm sure),  or just phased out and not available.  If you can get it, most places that do this kind of work won't do it for you,  may have to do it your self.  Have a great day  ----  Fritz

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Re: Dash Air Refrigerant

Reply #4 – July 30, 2018, 08:14:49 pm

I have a 100 lb. Cylinder of R 12.

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Re: Dash Air Refrigerant

Reply #5 – July 30, 2018, 09:07:02 pm

eBay still as R-12 1 pound cans for sale but well over 20 bucks per pound, they also have some drop ins much cheaper. R-12 is close enough to r-134a in capacity, will at least until you hit about 100 degrees ambient temps. The R-12 condenser with r-134a refrigerant starts getting a little small.

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Re: Dash Air Refrigerant

Reply #6 – July 30, 2018, 10:17:41 pm

I can get R-12 and the shop that provides it will service the R-12 units. I have all my Mercedes a/c  work done at the same place because they have it. It is not illegal.

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Re: Dash Air Refrigerant

Reply #7 – July 30, 2018, 10:51:37 pm

Randall what mbz you got? Isn't funny that the halongenated R-22 got banned in the Montreal protocol also the same year DuPonts patent ran out, huh? Inferior high pressure replacements claim a very slight better ozone depletion potential. $$$$$$$$$$$$$$. Super high pressure refrigerants seem to make stuff leak more.

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Re: Dash Air Refrigerant

Reply #8 – July 31, 2018, 12:14:27 am

In the next five years all manufacturers ( europe's has already) will stop using R-134a and therefore DuPont/Honeywell will quit producing R-134a refrigerant so you may start thinking about stocking up in the near future. New cars today are switching to HPO-1234yf refrigerant that has the same characteristic as R-134a, downside this gas is  slightly flammable and is about $70.00 per pound.

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Re: Dash Air Refrigerant

Reply #9 – July 31, 2018, 01:16:05 am

The ultimate goal is to make everything throw away every couple of years, it isn't about the environment!! New $$$$$$ VRF HVAC systems are total junk and totally reliant on complex circuit boards that are only supported a few years. A few years ago I had to make THAT phone call to a school to tell them it would be 8 weeks to get a failed circuit board because of  tsuanmi had wiped out the factory. School started 2 weeks late. Can you imagine telling leasing tenants the same! They have no limp mode.

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Re: Dash Air Refrigerant

Reply #10 – July 31, 2018, 02:50:32 pm

My MBZs are all 80s except one 91 S. I had one 83 300D converted to R-134a and the output was warmer than dog's breath.

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Re: Dash Air Refrigerant

Reply #11 – July 31, 2018, 04:21:32 pm

What about a hydrocarbon refrigerant like "Duracool 12a" which is a mixture of propane (79%) and isobutane (21%).
Some people are using 100% propane successfully.
Propane does not deplete the Ozone Layer and is inexpensive. A 16 oz can from Walmart will charge most automobile A/C's.
A long article about making your own propane/isobutane mix can be found at "http://www.possumliving.com/2012/08/propane-refrigerant-for-automotive-air.html"

I have propane/isobutane in my 1984 Toyota Supra.

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Re: Dash Air Refrigerant

Reply #12 – July 31, 2018, 04:25:42 pm

Note: that butane will not work in a car A/C system because the vapour pressure is too low, you must use isobutane.

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Re: Dash Air Refrigerant

Reply #13 – July 31, 2018, 10:53:16 pm

R-12 off ebay, but for that big of a system, it's going to take a boat load

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Re: Dash Air Refrigerant

Reply #14 – August 01, 2018, 12:07:02 am

I seen on the inter webs. They used the cans of compressed air for office use.. the one you use for blowing out a computer or keyboard

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Re: Dash Air Refrigerant

Reply #15 – August 01, 2018, 01:27:56 pm

Very interesting about the propane/isobutayn mix.

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Re: Dash Air Refrigerant

Reply #16 – August 01, 2018, 04:15:05 pm

R12 is illegal to produce any more, but is legal to use to repair existing systems. To buy requires a tech to have a MACS certification. Thou I have seen it sold "illegally" on eBay and craigs list. As they say it is only illegal if they catch you.
They are starting to crack down on illegal Freon sales, I know now my part supplier requires my certification on file before they will sell any Freon, be it R12, R134, or R1234

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Re: Dash Air Refrigerant

Reply #17 – August 01, 2018, 06:05:44 pm

I'm not sure I see a problem with 134a. Since 1994 all vehicles were out of the factory with R134a and seem to work just fine. Works fine in all of my vehicles including the RV. The only down side is that if you convert, the R12 has to be evac'd. But if it is already blowing warm air.........*shrug*......

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Re: Dash Air Refrigerant

Reply #18 – August 01, 2018, 07:59:30 pm

Just saying they caught some scrap metal theive stealing charged condensing units. Fined them $250,000.00 for that white cloud. 17 years 134a patent expires/ or has expired so guess what?

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