anyone know how to drain the AC system, and recharge it?

Anyone know how to check if there is no air in the system?

My AC is warm and they said needs to be drained and refilled inorder to get a full charge, I can charge it without draining it but wont get full.

 

yea we hook up a machine and evacuate all the freon out of it--then we charge the system to what it says on the hood a/c sticker--usually around 1.43 pounds of freon. always check for leaks though--u have to know y there is no charge.

 

When you do get the AC evacutated- make sure they put it under vacuum for about 20 min to see if it drops. If the vacuum drops then you know you have a leak. If it doesn't seem to drop its a very small leak and you will need to have DYE injected into the system. Have them recharge it- there is a sticker under the hood with the specs of how much R134a it takes. If you make it through summer with the AC working, come back when the AC stops to work good again and have them check for leaks with the black light. Don't settle for the electronic leak detectors as they are not soo accurate anyways- black light is the way to go. You might have gotten a stone to hit your AC condenser and its leaking there. My Sentra I bought off Ebay for 200 bux last year (94 XE 2 door auto) had that problem, I fixed it with a lil bit of JB weld and it held just fine :P

 

Interesting, with the drain, i didn't know they do flush out the refrigerant thorugh a vaccum equpiment.

 

Its not really a flush- they evacuate the old stuff out, put it under vacuum. Start the car up, put on the AC into MAX cold, and put the new stuff in. Once the compressor kicks on it will pull the refrigerant in by itself- sucking it in through the low side service port.

 

Can you do it yourself. Can you relieve the pressure by pushing in the tab inside the low side service port? Can you take out the old stuff without a vacuum

and refil it just with the pressure gauge and can, kit from checkers.

It says to fill it to 40 on the gauge from checkers?

Any questions or suggestions

 

By pushing the tab inside the shrader valve, you are releasing the stuff into the atmosphere and are poluting our planet ! If you got caught doing this, its a HUGE fine. I personally would never do a thing like that since I don't wanna loose my job or ASE and EPA AC certifications.

The cans you buy from a auto parts store suck, I doubt the whole AC service will cost ya more than 150 bux at a dealership. If it stops working on you, bring it back within 12 months or 12K miles and they have to look at it again for free.

 

I dont have any mechanic certifications so i dont have to worry about looseing them. I was just wondering if I bought everything I could do it myself without spending a 150 to get a shop to do it,

Isn't 134a better for the air, and not as harsh as r12

 

they are both just as harsh, only reason R12 is outlawed now- its been discontiuned by DuPont who made it- it was registered till 93, after that anyone could make it and goverment basically banned it.

 

Is it still possible to do it by yourself? Without buying the big expensive kits?

And refill it just with the gauge and some r134a, would the system automatically suck the coolent back into the system? or do you have force it back in there with a air system.

 

though not the best way, for $20 you can buy a can of 134a and oil charge that has a tap and guage attached. you need not drain the system first, unless you plan to put the proper amount of refridgerant into a vacant system
the cheesy guage you get w/ those kits is only accurate when the temp is around 78 degrees, on a hot day it will read high on a cool day it will read low.
turn your AC on full blast and attach it to the low side port, (the thicker of the 2 hoses, that should be located up top on the passenger side of the engine bay) and top off or fill the system, reading the guage when there in no freon flowing from the can (valve on can is closed) , most importantly dont overcharge the system its better to underfill rather than overfill.

if it drains out in a few weeks, pay the $150 to have dye put in so the leak can be found & repaired, if that $20 charge lasts the entire summer......