Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Evac system with compressor

ggenovez on Fri August 14, 2009 11:24 AM User is offline

Year: 1990
Make: GM
Model: Burb
Engine Size: 350
Refrigerant Type: r-12
Ambient Temp: 99
Country of Origin: United States

Hi all,

I don't have a evac machine. I do have gauges and a old helium party tank.

Anybody evac a system with the ac compressor, engine running? how is it done? can I do it with the equipment I have?

I need to replace the high side valve.

Thanks in advance.

HVargas on Fri August 14, 2009 12:25 PM User is offlineView users profile

Quote
Originally posted by: ggenovez
Hi all,



I don't have a evac machine. I do have gauges and a old helium party tank.



Anybody evac a system with the ac compressor, engine running? how is it done? can I do it with the equipment I have?



I need to replace the high side valve.



Thanks in advance.


Take it to a shop, have then evacuate the system, replace the valve and recharge it with the proper amount of refrigerant.



-------------------------
When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: Arizona Mobile Air


Edited: Fri August 14, 2009 at 12:26 PM by HVargas

ggenovez on Fri August 14, 2009 12:50 PM User is offline

Thanks Adam,

If the concern is moisture in the air, I have a cheap vacuum generator, but not a vacuum pump. So once I transfer it to the tank I can pull a vacuum. Shop wants more than a new pump. +I have to pay to get my r12 back .

HVargas on Fri August 14, 2009 12:55 PM User is offlineView users profile

Just make sure that both your hi and low side gauge's are showing ~30in/Hg and leave it on for at least 30 minutes. Let it sit for a while to make sure it holds vacuum and recharge with new virgin R12. DO NOT put back in the stuff you sucked into the helium tank. I can almost guarantee it is going to have air mixed in with it and then you have defeated the purpose of even pulling a vacuum.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: Arizona Mobile Air

TRB on Fri August 14, 2009 1:04 PM User is offlineView users profile

People have made up their own setups in the past some have worked some have failed. My suggestion is to get a vacuum pump and do the job correctly.

Mastercool 3 CFM Pump

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com


Edited: Fri August 14, 2009 at 1:05 PM by TRB

mk378 on Fri August 14, 2009 2:23 PM User is offline

You need a vacuum pump for any service that involves opening the system. Cheap vacuum generators are not suitable, they will leave air behind which will impair performance.

There are ways to recover refrigerant into a tank without a recovery machine. You must fully evacuate the tank first (again no cheap vacuum generator) or the refrigerant will have air in it. Then make the tank very cold with a chest freezer and wait several hours with the tank connected to the car for the refrigerant to condense in the tank. You will need to buy some R-12 to top up. Besides leaving some behind in the car, there's also no way to get all the refrigerant out of the tank to reuse it.

Trying to use the compressor to pump all or most of the refrigerant out risks compressor damage. They're not made to run dry. You probably have an R-4, which tend to seize up just from someone looking at them funny.

HECAT on Sat August 15, 2009 7:05 AM User is offline

Quote
Originally posted by: ggenovez
Hi all,

I don't have a evac machine. I do have gauges and a old helium party tank.

CAUTION: The helium party tank is a one way disposable container that is illegal and dangerous to refill. Many such tanks can have non removable valves and a check valve that will make it impossible to refill. Make sure it is empty, punch a hole in the rupture disk, and throw it in the scrap metal.

-------------------------


HECAT: www.hecatinc.com You support the Forum when you consider www.ackits.com for your a/c parts.

FLUSHING TECHNICAL PAPER vs2.pdf 

Cussboy on Sat August 15, 2009 10:06 AM User is offline

Quote
Originally posted by: TRB
People have made up their own setups in the past some have worked some have failed. My suggestion is to get a vacuum pump and do the job correctly.



Mastercool 3 CFM Pump

You wouldn't want to even try anything like recovering or evacuating with the engine and AC running - without refrigerant there'd be no oil circulation. That 3 cfm pump is a nice one, we bought one here about 2 months ago, very light, and has ports for both R-12 and R134a.

If you have the correct type of refillable cylinder, one can pull a vacuum on that, immerse in a dry ice-alcohol bath, and pull off your refrigerant into that, that's what I've done. As refrigerant gets drawn over by vacuum, it condenses to liquid by the cold, so the cannister still has vacuum so more gets pulled over.

Why do you need to replace the high side valve, can't a good cap seal this? It sounds like it stil has refrigerant in it (you talk about recovering it) so it mustn't be too bad or I'm missing something. And doesn't Tim sell a tool for replacing schraeder valves in place without losing refrigerant? Maybe a shop can do that.

If the shop wants more than a new pump, good time to buy a vacuum pump. Can't you rent a vacuum pump at some auto stores, maybe even AutoZone?

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.