A/C vacuum pumps ?

[bcjammerx]

I am needing to do some a/c work as my condensor has a hole in it. I have been trying to find some vacuum pumps and I have found many ranging in price from $75-$300...and some of these $75 ones are 1.5-2 cfm and some of the $300 ones are also in that range but usually 6cfm.

I am wondering if anyone else has any experience with using these and can give me some advice...as in...can I use a 1.5 or 2 cfm pump like this? Do these typically have fitting that will work with r-12 and/or r-134 systems? Is there anything special required to make it work for that application? (I know the fitting are different but mainly wanting to make sure all I need to do is buy the fittings...not like...drill and tap new holes or buy like 5 adapters of something)

These are what I am looking at;

FJC 6905 1.5 cfm Vacuum Pump (google search link)

and

Nex Tag search

lastly a google product search yielded these for ...Ten dollars? riiiiight
google product search

I have also seen the ones that you hook up to an air compressor, but from what I have read you have to have a mid sized tank (20+ gallons) as you have to apply a constant 90psi to get them to work...and they are good for 2-3 vacuum pulls. Plus you have to leave them on for a VERY long time...wasting a LOT of electricity.

More importantly I do not currently have an air compressor at all right now, I will be getting one in a few months but most likely not that large...so I am really wanting to get an electric vacuum pump if possible.

Any one have experience using these? When I worked at a shop I did not have to worry about such things, equipment was provided

[Gummiegorilla]

I just recently did a DIY on fixing A/C and the pump that i bought was from Harbor Frieght and total with tax it ran me $69.17 with a 20% off coupon. its a 2.5 CFM and pulls vacuum as quick as any name brand pump. Jut make sure you put a quality pump oil it , not that cheap ass oil that comes with it. here a link to the Them and to the coupon. only prob is that i dont think you can use the coupon online. i just printed it and took it in and it scans like any other coupon would but i guess thats only if you have a HF near you , other wise you might have to pay some shipping. Also the vacuum pump that you hook your air compressors up to are venturi style pumps and they dont work , period. i actually made a little testind device that shows they cant pull vacuum worth a damn. Not to sound biased or anything but hate those damn air pumps, nothing but agrivation lol. stick to electric, its a lot more quite and faster. Hope this helps.

Pump:
http://www.harborfreight.com/25-cfm-...ump-98076.html
Coupon:
http://dealspl.us/imageview.php?f=147363

Peace,
Gummiegorilla.

[visualpoet]

Also, do not use the vacuum pump on a system with refrigerant still in it. You could damage the pump and possibly injure yourself. When you vac it down after the repair, let it set for about fifteen to twenty minutes with the gauges attached to make sure it holds vacuum.
Other than that, gummie covered it pretty well.

[djkurious]

Also, do not use the vacuum pump on a system with refrigerant still in it. You could damage the pump and possibly injure yourself.

So how would you get all the refrigerant out? Just wondering.

[bcjammerx]

Awesome, it has both fittings too!!! That is what I will go with.

Yeah the impression I got with the ones you hook up to your air compressor is that you have to have a rather beefy air compressor...and even then...you'll be lucky to pull ALMOST full vacuum

Damn did not think about pulling the old refrigerant out...how AM I going to get all that crap out...

I am so used to using the machine at a shop...those things did it all! Even had gauges on 'em We used to do the a/c job right before lunch so we could let the vacuum set for a minimum 30 mins to make sure it held Hmmm...gonna have to bust open the old a/c book and find my notes too

[visualpoet]

I personally would never do this (it would cost me my hvac certification and a good chunk of change.) but you could slowly crack a fitting loose until it starts leaking, then wrap a couple shop rags around it (to cut down on the noise, frosty white cloud and refrigerant oils dripping.) and let it vent until it stops, since you don't have a recovery tank.
The one closest to the alternator would probably work best.

[bcjammerx]

I once thought my condenser had a hole in it so I was not too concerned about venting...i thought it already had. The lower rad support was smashed and the condenser is actually bent a little at the bottom... immediately after that incident my a/c stopped working, I "checked" the ports, there was SOME pressure but very little...of course the system had equalized the pressure by that time as well. I really should check all the sensors...I just assumed the system lost pressure and that was why it stopped working (clutch will not come on without sufficient pressure...of course...if that sensor is busted that would also keep it from coming on.

I will have to kick myself in the ass if all this time I just needed a new sensor of some sorts...but I will still need to pull, vac, and recharge even if that is all there is wrong.

Since I seem to still have old refrigerant...I guess I could try to make a recovery tank...sorta like a compressed air reserve tank...only for vacuum.

maybe I can hook up some gauges...if I have adequate pressure...just rig up something...if I have a full charge of r-12...I would rather keep r-12