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  #1  
Old 02-26-2008, 10:30 AM
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Question W123 R134a - how to discharge A/C system?

Can somebody describe how to do this?

All the A/C books I have seem to leave this detail out. I think my system may have all leaked out anyway, but I have no way of knowing. My A/C gauges are on the way from HF, but I want to disconnect my evaporator box tonight to replace stuff.

Original thread here...
W123 Testing the evaporator

Thanks,
dd

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  #2  
Old 02-26-2008, 10:33 AM
ForcedInduction
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Take off one of the charge port caps and briefly press in the valve to check it.

If there is gas take it to an A/C shop and have it evacuated and recycled.
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  #3  
Old 02-26-2008, 10:55 AM
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Quote:
Originally Posted by ForcedInduction View Post
Take off one of the charge port caps and briefly press in the valve to check it.

If there is gas take it to an A/C shop and have it evacuated and recycled.

Thanks Forced! Is the one right in view at the front of the engine ok?

Another question in all seriousness - why don't people discharge R134a systems at home? I thought R134a was ozone safe and is in commericial products like cans of computer duster air etc. R12 i know is a totally different story.

If people dump antifreeze into sewers, Im surprised DIY'ers don't think twice about discharging their systems at home when they have to. Especially since one of the main reasons to discharge a good AC system would be a blown engine.

Is there a reason? Is it really dangerous or difficult to do?

Only reason I ask is because my car is all apart and Id have to do some re-assembly to limp it to my indy.

Thanks again,
dd
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  #4  
Old 02-26-2008, 11:02 AM
ForcedInduction
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Originally Posted by dieseldan44 View Post
Thanks Forced! Is the one right in view at the front of the engine ok?
That one is good.

Quote:
Another question in all seriousness - why don't people discharge R134a systems at home? I thought R134a was ozone safe and is in commericial products like cans of computer duster air etc. R12 i know is a totally different story.
Is there a reason? Is it really dangerous or difficult to do?
Just like dumping coolant into the sewer knowingly venting an A/C system into the atmosphere is illegal (Double check on this). You will likely never get caught but it is still just as wrong.
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  #5  
Old 02-26-2008, 11:03 AM
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If something breaks, then discharging at home is "accidental". The reason to take it to a refrigerant recovery specialist is because refrigerants are poisonous and the newer types like R134A can cause heart arrythmia and mycardial infarction just by breathing it, long words for sudden death! The only one I would discharge myself without regret is Envirosafe since this is an environmentally friendly carbon based refrigerant. Envirosafe can be bought on the web and shipped directly to you. It smells like Pine Tar!

Envirosafe uses less energy to cool down and your performance and fuel economy will go up too!

Envirosafe is non-toxic and non-caustic.
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  #6  
Old 02-26-2008, 11:04 AM
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134a, while not being an ozone depleting gas, it is a greenhouse gas, and as such, it is required to recycle. a bunch of BS if you ask me, but I don't make the laws.
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Old 02-26-2008, 11:21 AM
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Thank you for the replies...makes sense. Ill give it a test and if by some miracle my system has something in it Ill take it in.

What doesn't make sense is that they use 134a for computer dusters and who knows what else.
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  #8  
Old 02-26-2008, 11:41 AM
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Quote:
Originally Posted by Knightrider966 View Post

Envirosafe uses less energy to cool down and your performance and fuel economy will go up too!

Envirosafe is non-toxic and non-caustic.
I am really thinking of trying Envirosafe in China. I have R134A in there right now and that just doesn't cut it in summer in Texas. Heck, even Freeze 12 {wagon} and R12 {Squash} aren't that great, but they at least get pretty much all that the system has to offer.
RLeo went to Envirosafe in Marlene last year if I remember correctly. Hopefully he will chime in as to the long term results......
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  #9  
Old 02-26-2008, 11:48 AM
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Quote:
Originally Posted by dieseldan44 View Post
Thank you for the replies...makes sense. Ill give it a test and if by some miracle my system has something in it Ill take it in.

What doesn't make sense is that they use 134a for computer dusters and who knows what else.
I don't believe that they use 134 in dusters, it's a flammable gas, probably a propane derivative... which is mostly carbon, which is also a greenhouse gas, so not sure still why they don't regulate it, but who knows really why stuff gets outlawed...
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  #10  
Old 02-26-2008, 12:43 PM
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r12 was outlawed because the patent rights ran out, look for 134 to do the same in about 10 years........ at least thats what my conspiracy theory freinds tell me.
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  #11  
Old 02-26-2008, 12:59 PM
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I'm considering Envirosafe to use instead of r-134a in my 300cd because r-134a doesn't quite cut in in hot and humid Saint Louis weather. It's a mix of propane/butane/etc, right? I would be worried about it leaking out and causing a fire or having the engine run away on the propane, has that ever happened, or is it pretty much "safe" to use?

I assume all that would need to be done is to have the r-134a in my A/C system removed and the Envirosafe put in... What about the oil in the compressor system though, should that be changed as well? My A/C system was overhauled with a new compressor, etc in 2000 and converted to r-134a.()
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  #12  
Old 02-26-2008, 02:16 PM
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Originally Posted by vstech View Post
I don't believe that they use 134 in dusters
HFC-134a is whats used in dusters. Thats why they get so cold during use.
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  #13  
Old 02-26-2008, 03:15 PM
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Dusters, air horn bottles, propellants for airbrushes and other various propellants are all typically HFC-134a. This chemical is nonflammable at room pressure (although it is flammable at a slightly higher pressure).

It is perfectly legal to vent 134a for these purposes.

It is illegal to vent ANY mobile air conditioner refrigerant. This includes R134a which is perfectly legal to vent in other circumstances. It also includes Envirosafe and other hydrocarbon refrigerants.
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  #14  
Old 02-26-2008, 07:48 PM
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my ac system had already 'illegally' disharged itself - no even a peep when i pressed in the fitting as forced described.

that explains why my compressor wouldnt kick in...

dd
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'83 300TD Cali Wagon 210k, wife's car
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  #15  
Old 02-26-2008, 09:48 PM
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Well that makes things easier. You'll just have to replace the receiver/dryer then pull a high vacuum for 30minutes before you charge it.

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