Is there a safe way to discharge the AC system?

[revhardSHO]

Only thing thats stopping me from dropping the engine. AC actually works and has pressure (60 lb @ low pressure port) so I need to figure out a way to discharge the system safley. I dont want kids with 11 fingers. The car is in my garage under the rest of the house, so I especially want to be careful... the entire family is above this mess. How toxic is this stuff? How do other sho chopper uppers deal with this?

Thanks
Silas

 

[Shoaz]

Freon or R-134a?

I don't think this is a good way to do it, but, FWIW, when I pulled the engine out of The Pumpkin I was going along merrily disconnecting things and pulled the clip off the connector for the high side of the condensor by the radiator. There was a BANG and a hissing sound and instantly I had R-134a lubricant all over everything.

"Ah", I thought, "probably shouldn't have done that."

Other than being a mess to clean up and smelling really bad, there doesn't seem to be any ill effects. I wouldn't recommend that method, and the R-134a really does smell pretty bad so be careful in an enclosed space.

Freon is highly highly highly non-toxic. A big reason that it was used for so long is that it is very safe stuff to handle, largely inert, etc., etc. Until somebody figured out that the patent was expiring and it therefore damages the ozone layer it was the ideal refrigerant. There are other lubricants and stuff mixed in with it, though, and I'm not sure whether they smell bad or eat flesh or whatever.

 

[revhardSHO]

I was going along merrily disconnecting things and pulled the clip off the connector for the high side of the condensor by the radiator. There was a BANG and a hissing sound and instantly I had R-34 lubricant all over everything.

"Ah", I thought, "probably shouldn't have done that."

Thanks for the reply, Its the new stuff, R-34a. (94 Opal ATX)
Ill take the mal to a condenser line and stand back. Open the garage door and turn the fan on. Wait a few minutes and go back to my merry work. Anyone want a 3.2?

 

[jelloslug]

I just used a long (18") screwdriver and pressed the valve down on the high side. This will keep you hands out of the way so there is no chance of frost bite (unlikely anyway). You may want to wrap the valve in a cloth to keep the oil from spraying everywhere.

 

[revhardSHO]

Only reason I was concerned is the refill bottles of R34a have huge warnings not to inhale the stuff or it could cause sudden death. I guess Im okay then?

Jelloslug,
I will get a shipping quote on all that stuff and let you know tomorrow.
edit: I want to see more pics of your car!

 

[Rob94]

I just used a long (18") screwdriver and pressed the valve down on the high side. This will keep you hands out of the way so there is no chance of frost bite (unlikely anyway). You may want to wrap the valve in a cloth to keep the oil from spraying everywhere.

Or you can do the responsible thing and bring it to an AC repair shop and ask them to properly evacuate the system. I doubt they'd even charge you for the service, as they get to reuse the recovered refrigerant.

 

[SHOman24v]

Wear a mask as you "vent"




Nah dont listen to me lol

 

[aaronsbiza]

Evacuate the gases through a tube that runs through a vat of water. This will scrub the gas of the toxic gases.

 

[revhardSHO]

Evacuate the gases through a tube that runs through a vat of water. This will scrub the gas of the toxic gases.

Easier said than done!

 

[sideSHO]

Easier said than done!

That may be an ok idea.
Just use the hose that these re-charge kits come with.
Cut the bottom out of an old R-134 can,and there you are.
Sounds good to me

 

[revhardSHO]

That may be an ok idea.
Just use the hose that these re-charge kits come with.
Cut the bottom out of an old R-134 can,and there you are.
Sounds good to me

I suppose I could splice my gauge back in once I have the system drained. Ill look into it more tomorrow.

 

[sideSHO]

I suppose I could splice my gauge back in once I have the system drained. Ill look into it more tomorrow.

You would'nt have to cut the hose,just the can.
Hook up the hose to the low side,and the other end to an opened can in water.
Acts like a cut hose without the cutting.
Don't know if that made sense or not.
Good luck.

 

[revhardSHO]

You would'nt have to cut the hose,just the can.
Hook up the hose to the low side,and the other end to an opened can in water.
Acts like a cut hose without the cutting.
Don't know if that made sense or not.
Good luck.

Sorry that didnt make sense! lol. The gauge I have simply reads the pressure, there is an outlet but its one way into the system (to charge it).
So I would have to cut the hose, splice in a length to drain the charge, then resplice the gauge back in. Do you see what Im saying?

 

[rangerj]

SMITHSIL,

If you are intent on venting the R-134a into the atmosphere, please do it in a well ventilated space. That warning on the cans is no joke. A cloud of that gas can displace the oxygen in your lungs and lead to serious problems.

If you are using a garage, then open all doors when you do it. I always use a portable fan to blow air and the gas away from me anytime I work with it. Any of the R-134a that is in liquid form can cause instant frost bite on the surface of your skin, and worst of all your eyes. Wear eye protection.

As indicated in your original post you are correct to be concerned about working with this chemical compound in a gasious state. Keep your loved ones out of the area you are working in until you are done. You should have someone nearby, but out of harms way, to provide assistance, or call for help if you are overcome by the gas. If you are careful this should not happen.

As for the patent on R-12, it was granted in the 1930s and would have run out about 50 years before the advent of R-134a being used in our cars. This crazy conspiracy myth just will not go away. rangerj

 

[revhardSHO]

Thank you RangerJ. Just the kind of reply I was hoping to get. I will have a few fans flushing the air away and out of the garage. You say the R34a displaces the oxygen in the lungs... what does this mean? Your lungs are unable to get o2 into your system? Any other nasty side effects I should know about?
Whats the best way to discharge the system? Right now Im thinking the water bucket method, but I think the high port pressure would just make a mess more than anything. The entire front end is off the car so I can just roll it out.

 

[revhardSHO]

Or you can do the responsible thing and bring it to an AC repair shop and ask them to properly evacuate the system. I doubt they'd even charge you for the service, as they get to reuse the recovered refrigerant.

Or you could read my first post.

 

[Shoaz]

As for the patent on R-12, it was granted in the 1930s and would have run out about 50 years before the advent of R-134a being used in our cars. This crazy conspiracy myth just will not go away. rangerj

My understanding is that a number of process and manufacturing patents were expiring related to Freon. Even though freon has been around for a long time, it wasn't commercialized very well until the 50s and 60s. Many of the manufacturing/process patents that enabled mass production were pretty key to the industry.

Again, that's as I understand it. Being personally in the middle of patent work related to large corporations, I have zero difficulty believing this. I think that had a lot to do with why asbestos went from being a miracle fire retardant and building material to the bane of OSHA and NHS as well.

Money makes the world go 'round, not altruism.

 

[rangerj]

From the Ford (Helm) service manual:
"The liquid refrigerant evaporates so rapidly that the resulting refrigerant gas will displace the AIR (including oxygen) surrounding the area where the refrigerant is released. TO PREVENT POSSIBLE SUFFOCATION IN ENCLOSED AREAS, ALWAYS DISCHARGE THE REFRIGERANT FROM THE REFRIGERANT SYSTEM INTO A GARAGE EXAUST COLLECTOR. ALWAYS MAINTAIN GOOD VENTILATION SURROUNDING THE WORK AREA".

Also note that the gas becomes a highly poisonous gas when it comes into contract with a flame. So, NO SMOKING or OPEN FLAMES WHEN YOU DO THE DISCHARGE. If you can roll the car out of the garage into the open air it would be best and IMHO safer.

When the system is not being pressurized by the compressor the high side and low side pressure are equal. The hose discharge method you describe (or whoever described it) will work. Good luck and work safely. rangerj

 

[SHOguy 92]

You say the R34a displaces the oxygen in the lungs... what does this mean? Your lungs are unable to get o2 into your system? Any other nasty side effects I should know about?.

I think it means you drown except you aren't under water? Anyways how I did it was just like jelloslug, screw driver and put a cloth over the valve, worked fine.

 

[aaronsbiza]

Because Freon gases are heavier than air, fluorocarbons can displace atmospheric oxygen, thus resulting in asphyxiation.