CruSGH

Alright, I just put together my a/c system(its hot out!) and i need to evac it(i havnt put the drier on just yet) tosee if there is any leaks. I have used a 5CFM vacuum pump before but will a 1.5 single stage vacuum pump be enough to evac a system down to ~ -28 mmHg?
Also can anyone explain what a micron rating is about? One i am looking at getting for myself has "200 Microns of Ultimate Vacuum"
Thanks in advance!


Modified by CruSGH at 12:34 AM 7/6/2006

Frozen E

read the vac pump's specs? Different manufacturers, different specs. I'm not doing your homework for you.

CruSGH

i know its 200 microns, im just wondering what exactly microns mean in that sense

Specifications: 110V, 60 Hz, 1.5 CFM free air displacement, 200 microns ultimate vacuum, 1725 rpm rotating speed and 1/4 Hp motor


Modified by CruSGH at 12:45 AM 7/6/2006

Frozen E

for an automotive application, 200 microns is plenty. Get a new dryer and accumulator while you're at it. Especially if your system has been open to the atmosphere for any amount of time.
Try to get all the oil out of your compressor and replace it with new stuff when you go to charge it up.
Refrigeration oil is very hygroscopic and will pull moisture out of the air and lock it in. Moisture in an AC system is bad joojoo.

CruSGH

is most of the oil thats in the system in the compressor? from what i have seen, i should pour hte oil in the compressor into a mesduring device and then put that exact amount back into the compressor?

this is a system that was converted to 134a

Frozen E

Yeah, deffinately get rid of any oil you can. The old oil used in R12 systems doesn't play well with 134A. Do some seraching on google for step by step how-to's on how to do a recharge on a car system.

CruSGH

sry i meant it wasallready converted but the person that did it i woudnt trust he did it right. ill get some new oil