A/C recharge question
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 41
Likes: 0
A/C recharge question
I have to replace the hose that comes off of the compresor on the A/C. I removed the old hose and now I was told by a friend that you can't just install the new hose and charge the system. You need to get the condensation out some how. Does anyone know the proper way to do this? I only want to do this once and not waste any product or money. Thanks to all in advance.
Charlie
Charlie
Burning Brakes
Joined: Sep 2001
Posts: 1,166
Likes: 0
From: Tulsa Ok
Anytime you open the system, you need to replace the drier as it will load up with moisture within a hour. So replace the drier and hose and pull a 28hg vacuum on the system for an hour. This will boil out the moisture in the system. Verify that the system holds the vacuum for at least an hour and you can recharge.
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
They make vacuums for this, or a guy on eBay sells plans to use an old refrigerator pump to build one.
No offense, but it sounds like you don't know much about HVAC systems. Without manifold gauges and some know-how, you can cause a lot of problems - best bet is to take it to an A/C shop and make use of their expertise.
No offense, but it sounds like you don't know much about HVAC systems. Without manifold gauges and some know-how, you can cause a lot of problems - best bet is to take it to an A/C shop and make use of their expertise.
Burning Brakes
Joined: Nov 2002
Posts: 952
Likes: 44
From: NC
Anytime you open the system, you need to replace the drier as it will load up with moisture within a hour. So replace the drier and hose and pull a 28hg vacuum on the system for an hour. This will boil out the moisture in the system. Verify that the system holds the vacuum for at least an hour and you can recharge.
http://www.napaautoparts.com/masterp...)+Assy+-+Remfd
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 41
Likes: 0
Correct Batman, Don't know much about HVAC systems but I am quite hand and mechanical. With the right tools and instructions I could handle it. Do they rent the vacuums at rental places? Does the system stay in the "vacuum" state when you disconect the vacuum? Is that all that needs to be done before recharging? Thanks for all the help people.
Heel & Toe
Joined: Feb 2007
Posts: 19
Likes: 0
From: North Port Florida
I don't know that much about auto HVAC, but I am a HVAC installer in residential and commercial buildings. I am not sure if the same thing applies to cars but, but first you might want to check for leaks by charging the system with nitrogen. If the nitrogen leaks, the refrigerant will to, so you need to fix the leaks. I have found that pulling a vacuum is not a guaranteed way to check the pressure of the system. Next evacuate all of the nitrogen and pull a vacuum with a vacuum pump which you can probably rent at a local HVAC supply house. That will pull all the contaminates out of the lines. Thats just my 2 cents. 
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
Correct Batman, Don't know much about HVAC systems but I am quite hand and mechanical. With the right tools and instructions I could handle it. Do they rent the vacuums at rental places? Does the system stay in the "vacuum" state when you disconect the vacuum? Is that all that needs to be done before recharging? Thanks for all the help people.
From personal experience, I struggled with the A/C system in an old driver of mine because I didn't have a proper set of gauges. I had a terrible time getting the pressure right.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
If you're not already on R134a, why not convert now??
btw, you might find this an interesting link...
http://www.id-usa.com/how_to.asp
btw, you might find this an interesting link...
http://www.id-usa.com/how_to.asp
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Intermediate
Joined: Jul 2006
Posts: 41
Likes: 0
OK, here is where I am...I got the plans for the home made vacuum pump. I tested the fridge compressor and it only pulls 26 in Hg. Is that OK? Also, do I need to have the pump run for the hour that I am testing the Vette a/c system or can I disconect it after I get it to the 26 in Hg?
PS
I'm going to convert to R134a.
PS
I'm going to convert to R134a.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
You need to pull 29 on a normal gauge for a long time. For my own stuff, I let it run overnite after I'm sure there are no leaks.
That is the only way you can boil off the moisture.
Moisture in AC is very very bad.
A thermister vacuum gage should really be used, water boils out at 1500 microns and you should try to get to around 600 microns.
That is the only way you can boil off the moisture.
Moisture in AC is very very bad.
A thermister vacuum gage should really be used, water boils out at 1500 microns and you should try to get to around 600 microns.
