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Ken's A/C ( the continuing saga of the 84 rebirth)

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RoyalViking

Guest
That's a relief, uh (realizing it was close to a pun) I mean I feel better knowing for sure. Thanks!

Roy
 
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1stiff84

Guest
Doc and Vig

Doc and Vig,

In an R-12 system, with 81 degrees ambient temp, I am getting 25/220 PSI lo/high at high idle (2k rpm) with the fan and A/C setting on max. Vent temp. is sub-40's. Compressor doesn't seem to stop.
What do you guys think?


Thanks Again,

Stiffy
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Get a temp gauge and stick it.

In the air vent... you want the temp to be OVER 32 degrees discharge air
(34-36 ish) if it is lower the condenser coil will freeze up ( making ice cubes )


It sounds like your right on the money...if anything you might be SLIGHTLY under charged... by like 1/2 lb or less....

Unless you are freezing up I would leave it alone... Vette compressors USUALLY do not cycle... unless you have Automatic temp control.


Vig~!
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Most important

Are you cold enough? Remember an A/C system can only drop that air about 17-20 degrees MAX..... so If it's 100 in the cabin... the best you can hope for is 80 and so on.

Vig!
 
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1stiff84

Guest
Thanks, Vig.

Vigman,

Thanks once again for all of your help. Temp. gauge in vent reads 38-39 F.
Thanks also for the A/C education. I didn't know an A/C system can only drop air about 17-20 degrees MAX.
Hope I get an opportunity to run into you sometime. I definitely owe you a pitcher.

Thanks Again,

Stiffy
 

vigman

Motor head!!!!
Joined
Feb 13, 2001
Messages
3,471
Location
Valencia, CA,USA
Corvette
88 Convert ( SOLD ) /1973 coupe 4 speed/1964 Vert!
Any time Stiffy

All part of the CAC full service package...

Hey wait...maybe we could have a CAC CA get together!


Hmmmmmm?

Vig!
 
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LarryBible

Guest
I agree with vigman. Don't touch it, just enjoy the cool and don't forget to keep the sweater in the car. You've got it right on the money.

Have a great day,
 
1

1stiff84

Guest
Doc and Vigman

Thanks for the feedback, Doc.

Hey Vigman, if something like a CAC CA get together gets planned, please let me know; I'd be very interested.

Thanks again,

Stiffy
 

Redbob

Well-known member
Joined
Dec 5, 2001
Messages
239
Location
Cross Roads, Texas, U.S.
Corvette
'89 dk red coupe
One trick I learned from a refrigeration mechanic friend of mine: after finding all the leaks you can, vacuuming down, verify the system will hold a vacuum overnight.
This is unfortunately no guarantee it'll hold pressure; I've had bad old hoses on a car that would hold vacuum but not pressure.

So then he charges the system up with leftover R-22 from home A/C service (obtained from another friend) and verifies that it will run and hold pressure with the R-22. R-22 will show up on those electronic freon leak-detectors.
Unfortunately, R-22 won't cool in an automotive system, but it will develop pressure.

NOW if the system is leak-free, it should hold R-12.
Regards,
R
 
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LarryBible

Guest
The method you describe using R22 is illegal unless you recover the R22. Very few auto shops will dedicate a machine for recovering R22.

A better way to use R22 to look for leaks, and a method that is legal, is to use 4 oz. of R22 and then build pressure with Nitrogen, up to about 200PSI. This is enough R22 to show up with a leak detector, and enough pressure to show up even high pressure only leaks. it is then legal to release this small amount of R22 into the atmosphere.

This method is approved by the EPA with the thinking that it's better to allow 4 oz. of R22 into the atmosphere as an environmental trade off against a leak remaining that allows a larger amount of more harmful R12 into the atmosphere.

As far as holding the vacuum, you should ALWAYS do a gross leak check after evacuating the system for a short time, by seeing that it will hold a vacuum for five minutes. If it will hold it for five minutes, it would be rare that it would not hold it overnight. As you pointed out vacuum does not show up leaks that will show up under pressure unless they are significant.


Good luck,
 

Redbob

Well-known member
Joined
Dec 5, 2001
Messages
239
Location
Cross Roads, Texas, U.S.
Corvette
'89 dk red coupe
"Illegal"?
That's a sick bird of prey, right?

How "illegal" does that rank compared to, say, running 120 on the Interstate?

"As you pointed out vacuum does not show up leaks that will show up under pressure unless they are significant."

That's my point exactly; what would you rather do, vent a little surplus R-22 to atmosphere, or find that your $30-per-12oz-can R12 has vented itself to atmosphere?

Sheesh..."illegal"!
 
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LarryBible

Guest
How does it compare to running 120 MPH on the interstate? Well, I expect the speeding fine would be a few hundred dollars. The fine for venting R12 or R22 is $25,000. I'll let you do the math.

I didn't pass the law, I don't agree with it, nor do I care whether or not you break it. I just thought everyone might be interested in knowing about it.

Have a great day,
 

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