Manual dischargeing the AC

[Untamed]

Where would a TECHNICIAN manually bleed the refrigerant from the AC system? I took a pic of the system in my TA and I'm not sure where a TECHNICIAN would bleed the system if the TECHNICIAN was unable to use the normal method of removing the coolant.

http://www.cardomain.com/memberpage/772583/2

The third pic towards the bottom of the page shows three different spots that could be opened. Which of these (if any) could be opened to remove the coolant?

[HardcoreZ28]

Dave....I've seen all kinds of "technicians" do all kinds of things with A/C systems. If you're not taking it somewhere to have it evacuated then your best bet is to crack open the line that goes into the drier...the large nut on the end of the rubber line that goes into the large metal cylinder near the firewall. Highly illegal.......if anyone is around.

[Little G]

also highly toxic, so don't breathe heavy or anything, but me and my "technician" bled mine

[foff667]

i thought the newer cars used something non toxic and that the old refrigerant they used in the 80's was???

[HardcoreZ28]

R12 is highly destructive to the ozone the new stuff 134(a) is a lot easier on it. I believe there is even something newer out now.

Dave....you are better off retrofitting for 134(a) when you refill. Basically you can just change the seals and you're good to go. 134(a) is about a quarter or less the price of R12.

[Untamed]

Thanks guys. Â*Any easy way for a "technician" to bleed the stuff out without freezing fingers? Â*Or is it as simple as it looks - grip the line with a rag and pliers on one end, then unscrew the nut slowly until it starts hissing?

EDIT: Retrofitting to 134(a), does it require all new hardware, costing hundreds? Or is it simply a few seals and a line or two, costing a little less than $200? Recharging a system by itself can cost nearly $150 right?

[HardcoreZ28]

simple as it looks...just make sure when you start twisting the nut off the mating end of the tube doesn't start to twist with it.

[84HOtransam]

Originally Posted by Untamed

Thanks guys. Â*Any easy way for a "technician" to bleed the stuff out without freezing fingers? Â*Or is it as simple as it looks - grip the line with a rag and pliers on one end, then unscrew the nut slowly until it starts hissing?

EDIT: Â*Retrofitting to 134(a), does it require all new hardware, costing hundreds? Â*Or is it simply a few seals and a line or two, costing a little less than $200? Â*Recharging a system by itself can cost nearly $150 right?

R-12 costs my dad wholesale about 30 bucks a pound...our cars need 3 pounds..

if you want to bleed the system just unscrew a line and let it leak out.. be sure to hold back on the oppsite side of the line (use a wrench for each side) because everything is aluminum and breaks easy..

its cheaper to top off an R12 system then it is to convert it to 134a but only if the system does not leak...

the a/c lines in my car were shot so i got new ones with all the orings i needed, a new evapotator (silver canister) and an oriface(like a inline filter)...the parts total was about 100 bucks..plus 90 for the lines(extremly hard to find for my car)..i drained most of the compressor oil and re filled it to spec.. it works beautifully...better then it did with the R-12

[HardcoreZ28]

The silver canister is not the evaporator...it's the drier. The evaporator is either the piece in the heater box or the one infront of the radiator...I forget which is which....the other is the condenser.

To refill a whole system 134(a) is much cheaper....I think it's like $12-$15 a pound now.

[Tru2Chevy]

Evaporator is in the heater box, condensor is in front of the radiator

- Justin

[HardcoreZ28]

That's what I thought since the compressor compresses the gas in liquid form and the evaporator turns it back to gas which causes the cold temp, then the condensor turns it back to liquid form before being compressed again.
Yay...physics is fun!

[Untamed]

Since this is a poor mans restoration, I'd rather just keep what I have and recharge the system after the car is up and running. If the cost of replacing and recharging the system is the same as simply recharging with R12 (yeah right, I doubt that) then I'll switch. Otherwise, I'll still contribute to depleating the ozone.

[HardcoreZ28]

Ok let me put it this way for you.

If you're planning on removing the AC system to paint the engine bay or anything else like that then you want to switch to 134(a). The retrofit kit doesn't cost that much and the freon is substantially cheaper. If you don't need to remove the AC stuff you might be able to just move the lines out of your way for the engine swap. Then you can just top it off with R12 if it's not too low or leaking.